×

Autonomy

Challenges

  • Safety constraints must hold across changing environments and long-running tasks.
  • Human intent can become difficult to trace through layered autonomous decisions.
  • Protocol failures may emerge only after rare sequences of otherwise valid actions.
  • System updates must preserve established guarantees and operating boundaries.

Problems We Solve

  • Invariant Modeling Represent safety boundaries and operating assumptions explicitly.
  • Protocol Checking Check transitions, permissions, and required responses.
  • Failure Simulation Explore exceptional paths before they occur in operation.
  • Boundary Validation Detect actions that leave an approved operating envelope.
  • Evidence Generation Produce traceable records for review and assurance.

Domain portfolio

Application patterns

Compare two formal-assurance approaches, then explore the domain workflows as interactive state machines.

Autonomous-system assurance concerns invariants, operating protocols, fail states, and preservation of approved boundaries as missions, environments, and software change. Verified readback can turn a narrow assurance claim into a type-correct proposition for deterministic review. These patterns emphasize traceable intent; type checking does not establish sensor truth, safety-case adequacy, or safe deployed behavior.
01 Uncrewed aircraft contingency-protocol authoring Explore pattern

System/use case

A mission-assurance workbench for an uncrewed aircraft system (UAS) that captures claims about containment, command-link degradation, lost-link behavior, and transition to a contingency mode. Autonomy and flight-safety specialists use it while reviewing the operational design domain and mission contingency plan.

Operational setting

The workbench sits beside mission planning, vehicle configuration, and hardware-in-the-loop simulation. Inputs can include named flight modes, flight-plan segments, containment regions, link-health states, contingency triggers, and allowed mode transitions. The formal setup represents only a curated abstraction of those inputs; it is not connected directly to flight controls and cannot authorize a launch or command the aircraft.

Decision/claim boundary

The checked object is a proposition about the modeled transition protocol—for example, that a declared loss-of-link transition enters a contingency state without first entering a prohibited mode. Whether the loss detector is calibrated, the containment volume is adequate, the transition is reachable in the deployed binary, or the aircraft is safe to operate remains outside that proposition. Release and operational authority stays with the accountable engineering and flight-operations roles.

Candidate checked statements

Illustrative controlled-English propositions for a future UAS setup include:

  • “Every transition from normal navigation after confirmed command-link loss enters a declared contingency mode.”
  • “No permitted contingency transition commands a waypoint outside the active containment region.”
  • “Pilot override remains permitted in every engaged autonomous flight mode.”

These are candidate schemas, not statements that the current tool or a deployed UAS already implements or proves.

Example architecture

Mission-planning and configuration services export stable identifiers and a versioned assurance view, not raw avionics data. A curator maps them to modes, events, regions, and relations such as mayTransition and overridePermitted. FF Scribe runs off the operational network and records candidates, diagnostics, readings, and decisions. A requirements repository versions accepted propositions; simulation, test, hazard analysis, and approval remain independent evidence channels. A human controls acceptance and requirements changes.

Where verified readback fits

The specialist writes the intended claim in natural language. The system maps it to the mission setup’s scoped proposition hole, and Agda checks syntax, scope, and types. If the checked type is within the configured readback slice, ff-readback produces a finite, audited deterministic family with semantic-rule provenance; unsupported structure fails visibly without a partial reading. The reviewer explicitly accepts the intended reading or supplies feedback for another bounded pass. Compilation alone does not establish an assurance claim.

Potential benefits

This pattern can expose omitted quantifiers, reversed transition direction, accidental overbreadth across modes, and ambiguity between detection and response. The accepted type and deterministic reading create a reviewable link between prose requirements and a formal artifact. Versioned statements can also focus regression reviews: a change to lost-link logic can be assessed against the exact claims whose vocabulary or transition assumptions changed.

Limits/adoption considerations

Type correctness establishes that a proposition is well formed in the chosen setup; it does not establish factual truth, conformance to an airworthiness policy, real-world flight safety, completion of a proof, or fidelity to the author’s intent. Those require, respectively, validated evidence, accountable policy and certification review, system safety engineering and test, proof terms or other verification evidence, and explicit practitioner confirmation. The setup must be governed like an assurance model: terminology, mode semantics, environmental assumptions, and version alignment need named owners. Sensitive mission data should be minimized because natural-language prompts and diagnostic logs can contain operational information.
02 Warehouse autonomous-mobile-robot traffic coordination Explore pattern

System/use case

A fleet-engineering review tool for autonomous mobile robots (AMRs) that expresses right-of-way, zone reservation, deadlock recovery, and human-intervention protocols. It targets claims that are usually scattered across fleet-manager configuration, programmable safety-controller logic, commissioning notes, and operational procedures.

Operational setting

In a fulfillment center or factory, robots traverse shared aisles, transfer points, charging bays, and human-access zones. A setup names zones, reservations, robot states, handoffs, and recovery actions. The tool supports design, commissioning, and change review, not real-time collision avoidance.

Decision/claim boundary

The formal claim concerns the abstract coordination protocol—for example, mutual exclusion over a modeled conflict zone or the availability of an escalation transition from a blocked state. It does not determine that localization is accurate, protective fields are correctly configured, braking distance is sufficient, or an installation satisfies a site safety standard. The controls engineer, machinery-safety specialists, and operations owner retain authority over commissioning and operation.

Candidate checked statements

Possible controlled-English propositions include:

  • “If one robot owns a conflict-zone reservation, every other robot is denied entry to that zone.”
  • “Every blocked mission can transition either to a cleared route or to operator assistance.”
  • “A robot in protective stop cannot receive a motion-authorizing dispatch transition.”
  • “Releasing a transfer-point reservation requires completion or cancellation of the associated handoff.”

These illustrate a potential domain setup; they are not deployed fleet rules or current readback coverage claims.

Example architecture

A read-only adapter derives a versioned logical snapshot from fleet configuration and zone maps. A registry names states, zones, reservations, and events. FF Scribe has no command path to robots or the fleet manager. Lifecycle records link accepted propositions to simulations, commissioning tests, and configuration revisions. Replay may test concrete traces but is not an Agda proof. Safety PLCs, onboard functions, and operators remain the active controls.

Where verified readback fits

An engineer describes the coordination property. Setup-scoped translation proposes one Agda type or clarifies ambiguous terms such as “blocked” or “owns.” Agda accepts or rejects the type on formal grounds. If the separate partial readback translation supports that structure, it deterministically renders binders and premises without reordering; otherwise the workflow fails visibly. The engineer confirms robot scope, zone, trigger, and outcomes or gives feedback. The result is a review item, not an enforced control.

Potential benefits

The workflow makes hidden protocol assumptions visible, particularly the distinction between reservation state, physical occupancy, and permission to move. It can give controls, fleet-software, and safety teams a shared artifact for change review. Explicit failed-state and recovery propositions can guide scenario selection for simulation and commissioning, while deterministic readings reduce dependence on model-generated paraphrases during approval.

Limits/adoption considerations

A well-typed mutual-exclusion statement is not evidence that all fleet traces satisfy it. Policy correctness depends on the site’s approved traffic concept; physical safety depends on validated sensing, stopping performance, protective equipment, and human procedures; proof completion requires a proof or exhaustive argument over the relevant model; intent requires explicit engineering acceptance. Vocabulary drift between the setup, vendor state names, and live configuration is a central adoption risk. Teams should also prevent acceptance workflows from becoming a substitute for hazard analysis or validation under representative congestion and failure conditions.
03 Automated-driving fallback and minimal-risk transition review Explore pattern

System/use case

A requirements-assurance assistant for an automated-driving stack that formalizes claims about feature engagement, operational-design-domain (ODD) exits, takeover requests, fallback progression, driver override, and transition to a minimal-risk condition.

Operational setting

Systems and safety engineers use the tool during concept development, safety analysis, and software-release impact assessment. A setup defines abstract feature states, ODD status, driver-availability observations, fallback events, degradation classes, and allowed transitions. Logs and scenario catalogs may supply evidence references, but the authoring session does not evaluate perception outputs or actuate the vehicle.

Decision/claim boundary

The proposition describes logical relationships in the approved abstraction, such as which transition must follow a declared ODD exit. It does not decide whether the vehicle is actually outside its ODD, whether a takeover request is timely, whether the minimal-risk maneuver is safe in current traffic, or whether the implementation conforms. Product release remains an accountable human decision supported by safety, test, and compliance evidence.

Candidate checked statements

Potential controlled-English propositions include:

  • “Every confirmed exit from the active operational design domain initiates fallback while the feature is engaged.”
  • “Driver override is permitted from every automated lateral-control state.”
  • “A severe degradation cannot transition directly to normal automated operation without recovery confirmation.”
  • “Every unresolved takeover request progresses to a declared minimal-risk transition.”

They are illustrative formalization targets, not verified properties of any driving system.

Example architecture

A versioned behavioral model remains separate from the production driving stack. Requirements, state-machine definitions, and hazard identifiers feed a curated assurance graph; simulation, track testing, and log analysis attach evidence references. FF Scribe checks a reviewed setup in isolation and returns acceptance records to requirements management. It cannot modify calibration, planning policy, or software. Safety engineers review traceability; release authorities decide lifecycle gates.

Where verified readback fits

The author states a narrow transition or invariant claim in natural language. Translation is constrained to the setup’s explicit state, event, and relation names. Agda rejects malformed applications and scope or type errors; it does not test the feature. The separate ff-readback translation either realizes a supported checked type through its finite, audited family—retaining premise order and scoped entities—or reports unsupported structure without a reading. The safety engineer compares the deterministic readings with the requirement and accepts only the intended one, or gives feedback that starts another bounded proposal-and-check loop.

Potential benefits

The workflow can distinguish an observed condition, declared state, and required response, and makes quantifiers and reachability reviewable. Vocabulary changes can flag accepted propositions for reassessment, connecting change impact to formalized intent and evidence.

Limits/adoption considerations

Type checking does not demonstrate factual correctness of ODD detection, correctness of the selected fallback policy, safe behavior in open traffic, proof of the proposition, or user-intent alignment. Those boundaries require validated sensing and test evidence, governance of the safety concept, vehicle-level verification and validation, proof construction or model checking with stated assumptions, and explicit author confirmation. Temporal and existential claims may exceed the current readback slice and must fail visibly rather than be flattened. Human-factors adequacy and driver-state uncertainty must stay explicit in the safety case.
04 Spacecraft onboard autonomy and safing-sequence assurance Explore pattern

System/use case

A protocol-authoring and review system for spacecraft fault protection, covering autonomy rules that isolate a suspect subsystem, preserve power-positive attitudes, inhibit conflicting commands, enter safing, and request ground disposition.

Operational setting

Flight-software, guidance-navigation-and-control, power, and operations specialists use it during procedure development and change control. A mission setup names monitored conditions, autonomy responses, command inhibits, subsystem states, safing milestones, and ground acknowledgements. Simulation and fault injection exercise concrete sequences.

Decision/claim boundary

Checked propositions concern the declared fault-management protocol and its abstract states. They do not establish that telemetry is truthful, thresholds are appropriate, a fault hypothesis is correct, power or thermal margins are adequate, or the flight implementation will execute the modeled path. Mission operations and the responsible engineering authorities decide whether a procedure or build is fit for flight.

Candidate checked statements

Illustrative propositions for a curated mission setup include:

  • “Every confirmed critical power fault transitions either to load shedding or to safing.”
  • “A command inhibited by an active fault response cannot be issued by onboard autonomy.”
  • “Every autonomous safing entry produces a ground-visible notification state.”
  • “Recovery from safing requires both fault-clearance evidence and an authorized recovery event.”

These are proposed statement forms only, not claims about a particular mission or implemented adapter.

Example architecture

A controlled repository holds a versioned fault-response graph with owners for each term. FF Scribe runs on the ground, isolated from commanding, and records the setup, type, check, readings, and decision. An evidence service links accepted propositions to analyses, fault-injection runs, tests, code, and anomaly dispositions. Existing controls protect command authorization; readback never crosses that boundary.

Where verified readback fits

An engineer enters the intended obligation. The model uses only the mission setup and clarifies uncertain conditions, phases, or quantification. Agda checks the type. For a structure supported by the configured profile, ff-readback derives audited deterministic readings while preserving configured constants and premise roles; unsupported structures fail visibly. A qualified practitioner accepts the intended meaning or gives feedback. Confirmation neither approves a flight rule nor uploads a command.

Potential benefits

Formalized, readable claims can help multi-discipline teams review sequences whose hazards arise only after combinations of individually valid responses. They make recovery preconditions, command inhibits, and ground-handoff expectations easier to compare across flight-rule, software, and test baselines. Deterministic readback also supplies a stable human review artifact for anomaly retrospectives and change-control packages.

Limits/adoption considerations

Type correctness is only structural validity inside a setup. Factual telemetry validity, mission-policy correctness, vehicle safety, proof completion, and intended meaning each need separate evidence and authority. The abstraction must represent concurrency, stale observations, timing, and partial failures when they matter; a simple transition graph may otherwise conceal mission-critical behavior. Vocabulary and evidence links require long-lived configuration control. Unsupported temporal or existential constructions must be reported explicitly, and sensitive mission information must be protected in prompts, artifacts, and diagnostic logs.

Applicability frame

MLTTDB is most plausible here as a design-time or release-time assurance layer for finite, source-controlled configuration sets. Proof-assistant source owns row types, table declarations, invariants, and proofs. The SQLite term store owns ordered source-language records, UUIDs, projection values, language metadata, and discovered table metadata. It can orchestrate verification, but Agda, Lean, or Rocq performs semantic checking. Agda currently supports finite table lookup by literal UUID in stored rows; the Lean and Rocq preprocessors validate generated definitions but do not provide that lookup facility.

Current data mode checks fetched rows as separate definitions; it does not expose a table to application proofs as an enumerable, first-class collection. Whenever an example below claims whole-snapshot coverage, uniqueness, or graph acyclicity, the architecture therefore assumes either a finite domain declared in proof source or an external snapshot compiler that emits a reconciled aggregate manifest/certificate term. The proof assistant checks that aggregate term, while external reconciliation establishes that it represents the table export supplied for release.

Telemetry ingestion, map or world-model construction, identity and access, source-system reconciliation, command dispatch, runtime enforcement, incident handling, and formalization review remain production components outside MLTTDB. A successful proof-assistant run establishes only the properties encoded over the supplied records and assumptions; it does not establish that sensors describe the real world correctly or that a deployed controller implements the checked model.

01 Warehouse AMR mission-release policy pack Explore pattern

Operational context

A distribution centre may run heterogeneous autonomous mobile robots (AMRs) under a warehouse execution system (WES) and fleet manager. Mission release depends on vehicle capability, payload class, aisle direction, pedestrian-zone status, lift or door interfaces, battery reserve, and recovery policy. These constraints are often distributed across map annotations, fleet parameters, commissioning documents, and WES rules. A bad configuration release can permit an infeasible route class, omit a required hand-off, or assign a recovery mode that conflicts with a zone’s access policy.

Why MLTTDB fits

The assurance target is a bounded configuration baseline, not live traffic control. Tables can represent mission classes, robot capabilities, zone policies, allowed transitions, and exception responses. Proof definitions can state that every releasable mission has compatible payload and locomotion capabilities, that entry to a controlled zone has a defined authorization and exit, and that every modeled degraded state terminates in a permitted recovery or human-assistance state. Stable UUIDs are useful when policy rows are edited or reordered while external release records retain identity.

Example architecture

WES/map/fleet exports -> reconciliation + review -> MLTTDB term store
                                                     |
proof-owned schema + invariants ---------------------+
                                                     v
                                           Agda/Lean/Rocq check
                                                     |
                                      signed release report + bundle
                                                     v
                                      fleet-manager deployment pipeline

An external adapter normalizes approved WES mission templates, map-zone identifiers, and vendor capability codes into reviewed source-language records. The term store preserves their order, UUIDs, and metadata. A proof-assistant module supplies the domain model and release predicates; CI or the store’s verification endpoint invokes the compatible checker. A separate deployment pipeline correlates the successful report with exact source exports and the fleet-manager bundle.

Representative typed artifacts

  • RobotProfile, including drive envelope, payload interface, and supported stop or recovery modes.
  • ZonePolicy, with access class, required interface handshake, and permitted mission states.
  • MissionTemplate, referencing a route class, payload class, and required recovery policy; Agda rows may use finite UUID lookup for controlled references to earlier tables.
  • TransitionRule and FailStateDisposition, separating normal progression from blocked, degraded, and manual-recovery outcomes.
  • A ReleaseManifest aggregate term, reconciled to the exported row UUIDs, carrying a Releasable witness or decidable check over the complete approved pack represented by that term.

Checks and evidence

Checks can cover reference closure, unique ownership of zone permissions, capability compatibility, absence of unsupported state transitions, recovery coverage, and declaration-order/acyclicity requirements for Agda table dependencies. Negative fixtures should include unknown policy references, missions with insufficient capability, missing degraded-state dispositions, and transition cycles forbidden by the formal model. Evidence should retain the checker version, proof source revision, database snapshot identifier, ordered record UUIDs, generated source where applicable, process output, and the deployment bundle digest. This is reproducible release evidence, not an immutable audit facility supplied by MLTTDB itself.

Potential benefits

The approach can expose configuration interactions before commissioning, replace spreadsheet joins with typed references, and make operational assumptions reviewable by controls and warehouse engineers. It can also make fleet or map upgrades easier to compare: unchanged policy identities remain stable, while failed proofs localize which modeled obligation no longer holds.

Deployment boundary

The fleet manager, safety-rated protective devices, traffic arbitration, localization, braking, and human exclusion controls remain authoritative at runtime. MLTTDB does not ingest telemetry, reserve routes, release missions, or guarantee collision avoidance. Deployment requires site acceptance testing, vendor-supported configuration controls, cybersecurity review, and qualified safety assessment of both the formalization and the physical installation.
02 BVLOS inspection-drone contingency-envelope release Explore pattern

Operational context

A beyond-visual-line-of-sight inspection operation coordinates aircraft, payload, command-and-control (C2) links, navigation services, weather sources, ground risk controls, and remote-pilot procedures. Before a mission profile is made available, the operator must reconcile aircraft configuration with route segments and contingency responses for degraded navigation, loss of C2, energy shortfall, geofence approach, payload fault, or unavailable recovery sites. The relevant envelope varies by aircraft and approved concept of operations; it should not be inferred from generic rules.

Why MLTTDB fits

MLTTDB can check a finite, reviewed mission-policy pack at configuration release. Tables can encode aircraft capability profiles, route-segment classes, recovery sites, trigger categories, and contingency procedures. The proof module can require that each modeled trigger in each flight phase maps to an authorized response, that a response’s prerequisites are compatible with the aircraft and segment, and that escalation never silently returns to nominal autonomy. This use exploits typed, ordered records without pretending that a static model captures live airspace or meteorology.

Example architecture

approved ConOps + aircraft config + route design
                    |
                    v
        domain adapter and accountable review
                    |
       MLTTDB policy/configuration database <--- proof-owned flight model
                    |
        project CI invokes proof assistant
                    |
     assurance dossier + approved profile digest
                    v
          operations planning platform

The adapter resolves identifiers from configuration management, route design, and procedure repositories and produces a candidate baseline. MLTTDB stores proof-language rows; the proof assistant checks their modeled relationships. An assurance service packages results with the exact flight-profile digest. The operations platform accepts only a separately authorized baseline and performs its own current-data and authorization checks.

Representative typed artifacts

  • AircraftConfiguration, capturing approved propulsion, navigation, C2, and recovery capabilities as abstract capabilities rather than raw telemetry.
  • FlightPhase and SegmentEnvelope, with permitted modes and declared operational assumptions.
  • ContingencyTrigger, RequiredResponse, and EscalationTarget records.
  • RecoverySiteCapability linked to applicable segment and aircraft classes.
  • A ContingencyCoverageManifest aggregate term, externally built and reconciled to the profile export, enumerating the phase-trigger pairs, responses, recovery sites, and row UUIDs covered by release checks.
  • Proof obligations such as trigger coverage, response precondition satisfaction, monotone escalation, and no modeled path to an unhandled terminal state.

Checks and evidence

A release suite can test that all referenced recovery sites and response procedures exist, every phase-trigger pair has exactly the intended coverage, energy or navigation-dependent responses declare their prerequisites, and no contingency path depends on a later or cyclic definition. Scenario fixtures should exercise loss-of-link during multiple phases, a recovery site withdrawn from the baseline, conflicting response priority, and an aircraft variant missing a required capability. Evidence includes proof/checker revisions, accepted and rejected fixtures, ordered row identity, source export hashes, and the reviewed assumptions attached to the mission-profile version.

Potential benefits

Typed contingency packs can reveal coverage gaps and variant drift earlier than simulator or flight-test execution, while giving remote pilots and safety assessors a precise inventory of modeled responses. Stable identities also support impact analysis when one recovery site, aircraft configuration, or procedure changes. The proof artifact can complement simulation by showing exhaustive coverage over the finite modeled categories.

Deployment boundary

MLTTDB neither obtains current weather or airspace data nor authorizes BVLOS operations, computes flight trajectories, commands the aircraft, or executes contingencies. Those duties stay with approved operational systems and accountable personnel. Regulatory interpretation, airworthiness, operational authorization, human-factors assessment, simulation, and flight testing must be performed by qualified specialists for the applicable jurisdiction and operation.
03 Industrial robotic-cell changeover interlock baseline Explore pattern

Operational context

A flexible manufacturing cell may combine robots, positioners, tooling, conveyors, machine vision, process equipment, and safety PLC functions. Product changeover selects recipes, tools, safe positions, guarding modes, and handshake sequences. Controls engineers need assurance that an approved changeover baseline does not enable a process step before the required tool, fixture, zone-clear, and equipment-ready conditions are established, and that aborted changeovers have defined recovery states.

Why MLTTDB fits

The finite object is the controlled recipe/interlock catalogue released to the cell, not the PLC scan-cycle state. MLTTDB tables can carry equipment profiles, recipe phases, permissive groups, handshake contracts, and recovery plans. An external release compiler also emits a CellBaselineManifest aggregate term and reconciles its UUID list and digest with the table export. Proofs over that term can establish structural properties across the represented catalogue: required interlocks precede hazardous commands in the abstract sequence; mutually exclusive modes are never demanded together; every abort state has a manual or automatic recovery disposition; and each recipe uses tooling rated for the modeled operation class.

Example architecture

PLM/MES recipe + PLC interface dictionaries + safety design
                          |
                controlled reconciliation
                          v
                MLTTDB candidate baseline
                          |
              proof assistant verification
                          v
         change-control evidence and codegen inputs
                          |
             PLC/robot offline validation -> site release

Engineering adapters map PLM recipe identifiers, MES product variants, and controls tags to a reviewed vocabulary. MLTTDB stores the resulting typed source rows and can orchestrate their verification. A separate generator may consume an accepted baseline, but its output is independently reviewed, compiled, simulated, and commissioned against the actual PLC and robot programs. No proof-language record is sent directly to an actuator.

Representative typed artifacts

  • EquipmentCapability and ToolingCompatibility catalogues.
  • RecipePhase with abstract entry conditions, commanded operation class, and completion indication.
  • PermissiveGroup, distinguishing process permissives from safety-rated protective functions.
  • HandshakeContract for producer/consumer request, acknowledge, timeout, and abort states.
  • RecoveryPlan and proofs of phase sequencing, interlock coverage, exclusive mode selection, and recovery completeness.

Checks and evidence

Checks should reject dangling equipment references, unsupported recipe/tool pairs, contradictory mode demands, missing timeout outcomes, commands without modeled prerequisites, and recovery graphs that cycle without an approved operator intervention state. Test baselines can model loss of a ready signal, tool-identification mismatch, partial changeover, and an obsolete device profile. Review evidence ties checker output and generated definitions to the recipe revision, safety-requirements revision, software build, and offline simulation campaign. The formal model should make explicit which PLC timing, diagnostic, and failure assumptions it abstracts away.

Potential benefits

This separates cross-equipment consistency checking from vendor-specific implementation syntax, allowing automation, manufacturing, and safety engineers to review one typed baseline. It may reduce late discovery of variant-specific omissions, improve traceability from a permissive to the recipes that depend on it, and make change impact visible when tooling or interface contracts are revised.

Deployment boundary

Safety PLC logic, emergency stopping, protective devices, drive safety functions, lockout/tagout procedures, and validated robot programs remain the real safeguards. MLTTDB is not a safety controller, does not monitor I/O, and does not certify generated PLC or robot code. A release still needs the applicable machinery risk assessment, functional-safety lifecycle activities, offline and on-cell testing, configuration control, and authorized sign-off.
04 Tool-using AI agent protocol-assurance service Explore pattern

Operational context

An enterprise AI agent may call search, ticketing, code, messaging, or data tools across multi-step tasks. Its orchestration policy must constrain which agent role can invoke which tool, what data classification is permitted, whether human approval is required, and how failures, retries, and compensating actions behave. Prompt-only descriptions are difficult to audit, especially when a new tool or workflow introduces an action path that bypasses an approval boundary.

Why MLTTDB fits

The policy catalogue is finite and changes under release control. Row types can represent roles, tool capabilities, protocol states, approval requirements, data classes, and failure dispositions. Proofs can check that every executable transition has an authorization basis, privileged effects require the modeled approval state, terminal failures cannot silently resume, and compensating actions exist for modeled partially completed operations. Here MLTTDB can support both release-time catalogue checks and an internal verification service for proposed workflow definitions; it is not the runtime policy decision point.

Example architecture

tool registry + IAM policy + workflow definitions
                       |
             normalization and owner review
                       v
             MLTTDB protocol catalogue <--- proof-owned state model
                       |
             verification API / release CI
                       v
             approved policy-bundle digest
                       |
       agent orchestrator + runtime policy engine + audit pipeline

External connectors reconcile canonical tool, principal, and data-class identifiers. The term store retains reviewed proof-language policy records, while the proof assistant evaluates protocol invariants. CI publishes a result bound to the proposed bundle. The orchestrator and policy engine load only a separately authorized bundle and enforce decisions using authenticated runtime context; an observability pipeline records actual actions.

Representative typed artifacts

  • PrincipalRole, ToolCapability, and EffectClass, including read, mutation, external communication, and irreversible-effect distinctions.
  • ProtocolState and Transition, with initiator, preconditions, effect, next state, and failure state.
  • ApprovalRequirement and DelegationScope, tied to an external IAM policy identity rather than invented by the agent.
  • CompensationContract for operations whose effects can be reversed or explicitly cannot be reversed.
  • A ProtocolBundleManifest aggregate term, reconciled to the tool registry, IAM-policy snapshot, and exported row UUIDs, materializing the transition graph used for bundle-wide reachability and privilege checks.
  • Proofs of least modeled privilege, approval-before-effect, failure closure, and absence of forbidden state paths.

Checks and evidence

Verification can reject unknown tool references, privilege escalation through delegation, an external side effect reachable before approval, retries of an operation classified as non-idempotent without a disposition, and failure states with outbound privileged transitions. Counterexample fixtures should cover confused-deputy paths, stale approval, tool substitution, partial completion, and compensation failure. Evidence links the checked row UUIDs, proof source, checker output, IAM/tool-registry snapshots, workflow-bundle digest, and reviewer approvals. Actual runtime traces must be captured and reconciled elsewhere.

Potential benefits

The typed protocol catalogue gives security, platform, and workflow owners a shared object for reviewing authorization and failure behavior. Exhaustive checks over modeled states can find rare multi-step bypasses that per-tool unit tests miss, and stable row identities improve impact analysis as tools and approval policies evolve. The same evidence can gate rollout of a workflow variant without coupling the policy model to one agent framework.

Deployment boundary

MLTTDB does not authenticate principals, inspect prompts, prevent prompt injection, authorize a live call, execute compensation, or provide an immutable action log. Runtime IAM, policy enforcement, sandboxing, secrets management, egress controls, human approval UX, and incident response remain mandatory. Security and safety specialists must review whether the modeled states and effects faithfully cover each concrete tool integration.

These read-only, pan-and-zoom models expose three abstraction levels for each workflow. They are explanatory examples, not live operational or decision systems.

01

Agentic Change Executor

About this workflow

This example represents an autonomous agent carrying out a production infrastructure change under bounded authority. It separates a requested outcome from the plan, approval, execution capability, rollout observations, and final acceptance. That separation is essential when an agent can call deployment, configuration, identity, or cloud-management tools: an apparently reasonable objective must not become permission to alter unspecified resources.

The normal campaign begins by parsing the desired outcome, prohibited effects, target resources, dependency boundaries, success measures, and rollback conditions. The proposed sequence of tool calls is exercised against a read-only snapshot, checked for permissions and resource invariants, and revised if targets or ordering are ambiguous. Authorization is then bound to the verified plan digest and expressed through scoped, expiring capabilities. Execution proceeds in bounded batches, with health signals, invariant checks, checkpoints, and observations recorded after each batch. Outcome verification compares the observed environment with success criteria, probes dependencies for regressions, and assembles a trace from intent to result. Only a verified outcome closes as accepted.

The machine makes failure containment explicit. An invalid simulation returns for replanning before authority is issued. A breached invariant during rollout, or a regression found during outcome verification, enters rollback recovery. Unused capabilities are revoked, the latest verified checkpoint is restored, and recovery invariants are checked. The campaign may return for reauthorization and resume, or close after a verified rollback. These controls matter to platform engineering and change-management teams because they limit blast radius, prevent approval drift after a plan changes, and preserve evidence that the actions actually performed were the actions reviewed.

Layer 1 — Change campaign stages

This layer is the campaign view for a service owner, change manager, or incident commander. It shows proposal, verification, authorization, execution, outcome review, rollback, and closure, including the only permitted routes back to an earlier stage. It intentionally hides individual tool calls so governance reviewers can focus on authority, acceptance, and recovery boundaries.

Layer 2 — Authorization and rollout protocols

This layer describes the operating procedures that make autonomous change safe: defining prohibited effects, simulating against a snapshot, binding approval to a digest, issuing short-lived capabilities, batching rollout, checkpointing, probing dependencies, and validating recovery. It is suitable for runbooks, policy-as-code reviews, and control design. Provider-specific API payloads and command syntax are outside this layer.

Layer 3 — Tool-level actions

This layer exposes the concrete actions and observations performed by the agent, such as identifying resources, checking permission scope, applying an approved batch, monitoring health, revoking unused credentials, restoring a checkpoint, and retaining the execution trace. It supports dry-run tests and forensic replay. It deliberately excludes internal model reasoning and vendor-specific tool implementations; the safety contract is defined by observable calls, results, and enforced boundaries.
02

Inspection Drone Operation

About this workflow

This example describes an unmanned inspection sortie from planning through evidence closure. The aircraft must collect usable sensor data while staying inside approved airspace, standoff, altitude, weather, control-link, and energy limits. The machine frames those limits as operational protocols rather than relying on the autopilot to make an unconstrained best effort.

The planned path begins with waypoints and inspection objectives, together with the applicable airspace, daylight, weather, and site constraints. Launch clearance verifies the command link, return-position fix, battery reserve, geofence, and approved flight plan before arming. The aircraft then follows its authorized altitude corridor to the asset, continuously tracking link quality, traffic, obstacles, and remaining energy. On station it stabilizes at each viewpoint, acquires the required imagery or measurements, checks data quality, and maintains its prescribed standoff. A planned return selects a route that fits the current energy margin, verifies that the landing zone is clear, and ends with touchdown and disarm confirmation. Closure reconciles the collected dataset against the inspection plan.

An aircraft is never assumed to continue simply because it is airborne. A rejected clearance returns the sortie for replanning, while cancellation before launch can close it without flight. Transit and inspection anomalies enter a common emergency response where link loss, worsening weather, navigation error, traffic conflict, or low energy is classified. Depending on the remaining safety envelope, the response can hold, return, divert, land, or resume the inspection after bounded recovery. The autonomous decision and any remote-pilot intervention are retained. These controls matter to UAS operators because a valid inspection objective does not override airspace authorization or safe recovery, and because flight logs must explain why the aircraft deviated from the original plan.

Layer 1 — Flight operation phases

This layer gives the remote pilot, mission commander, or operations manager the sortie-level picture: planning, clearance, outbound transit, inspection, return, emergency response, and closure. It highlights when authority changes and where an operation may be aborted or recovered. It intentionally omits waypoint commands and individual sensor checks so the overall flight disposition remains readable.

Layer 2 — Airborne safety protocols

This layer describes the procedures used within each phase: checking geofence and reserve before launch, monitoring link and traffic in transit, maintaining standoff on station, and choosing hold, return, diversion, or landing during an anomaly. It contains the operational decision points expected in a flight manual or safety case. It excludes low-level stabilization mathematics and raw telemetry streams.

Layer 3 — Autopilot actions

This layer shows the executable observations and actions behind the protocols, including loading constraints, arming the cleared plan, climbing within the corridor, avoiding detected obstacles, quality-checking captures, selecting an energy-feasible return path, and recording fail-state decisions. It supports simulation and test coverage. Airframe-specific control loops, radio packets, and sensor-driver behavior are intentionally left to the deployed autopilot implementation.
03

Autonomous Warehouse Fulfillment

About this workflow

This example represents a robotic pick-and-deliver mission in a shared warehouse. It treats the mission as more than motion between two coordinates: inventory custody, aisle reservations, payload limits, separation from people and equipment, and battery reserve must remain valid from dispatch through confirmed handoff. The machine therefore makes the operational authority given to the robot explicit and bounded.

The normal path starts when the warehouse control system validates a pick task, destination slot, robot allocation, and payload assignment. Route authorization then checks aisle geofences, traffic reservations, load limits, and energy margin before issuing an approved route envelope. During autonomous execution the robot localizes against the current map, navigates the reserved segments, responds to obstacles, and secures the requested unit. At the destination, handoff verification scans both payload and location identifiers and waits for inventory acknowledgement before closing the mission and reconciling the stock movement.

The return paths are as important as the happy path. An infeasible route goes back for task revision rather than being dispatched. A route, grasp, proximity, or low-energy fault moves execution into a safe-stop recovery state while payload custody is preserved. A mismatched destination or inventory scan is quarantined instead of being accepted as delivery. Recovery can lead to a newly authorized route, a supervised handoff, or closure as an unrecoverable mission. These controls matter because a locally plausible robot action can still violate fleet traffic rules, lose chain of custody, or create an inventory discrepancy. Recording invariant checks and operator interventions also gives operations and safety teams a usable incident trail.

Layer 1 — Mission lifecycle

This layer is the view a fulfillment operations lead would use to follow the job from mission request through route authorization, autonomous execution, handoff, recovery, and closure. It shows the major custody and accountability boundaries and the permitted loops between them. It intentionally excludes individual map updates, scans, and actuator commands so a reviewer can see whether the mission followed an authorized operational path without controller-level noise.

Layer 2 — Robot operating procedures

This layer expands each lifecycle state into the procedures carried out by the warehouse control system, fleet manager, robot, and operator. It includes task and slot validation, reservation checks, safe-stop classification, supervised recovery, and inventory reconciliation. It is the right scope for runbooks and exception handling. It does not model individual sensor samples or motor-control cycles; those details are summarized as procedure outcomes and invariant checks.

Layer 3 — Controller actions

This layer exposes the concrete actions that produce each procedural result: acquiring a local map, tracking obstacles, securing the unit, scanning identifiers, retaining the payload during a stop, and archiving intervention evidence. It is useful for controls engineering, test design, and trace reconstruction. Continuous control laws, vendor-specific message formats, and raw telemetry are deliberately outside the example; they can be attached beneath these actions in an implementation-specific model.
Interactive state machine

Workflow demo

Skip to content

Domains

Autonomy

Autonomy rules involving invariants, protocols, and fail states.

  • invariants
  • protocols
  • fail states

Problems we solve

Checked boundaries and evidence

  • Safety constraints must hold across changing environments and long-running tasks.
  • Human intent can become difficult to trace through layered autonomous decisions.
  • Protocol failures may emerge only after rare sequences of otherwise valid actions.
  • System updates must preserve established guarantees and operating boundaries.
Invariant Modeling

Represent safety boundaries and operating assumptions explicitly.

Protocol Checking

Check transitions, permissions, and required responses.

Failure Simulation

Explore exceptional paths before they occur in operation.

Boundary Validation

Detect actions that leave an approved operating envelope.

Evidence Generation

Produce traceable records for review and assurance.

Application patterns

Imported product records

These panels use the same generated application portfolio as the desktop workbench.

FF Scribe4 patterns
Autonomous-system assurance concerns invariants, operating protocols, fail states, and preservation of approved boundaries as missions, environments, and software change. Verified readback can turn a narrow assurance claim into a type-correct proposition for deterministic review. These patterns emphasize traceable intent; type checking does not establish sensor truth, safety-case adequacy, or safe deployed behavior.
01Uncrewed aircraft contingency-protocol authoring

System/use case

A mission-assurance workbench for an uncrewed aircraft system (UAS) that captures claims about containment, command-link degradation, lost-link behavior, and transition to a contingency mode. Autonomy and flight-safety specialists use it while reviewing the operational design domain and mission contingency plan.

Operational setting

The workbench sits beside mission planning, vehicle configuration, and hardware-in-the-loop simulation. Inputs can include named flight modes, flight-plan segments, containment regions, link-health states, contingency triggers, and allowed mode transitions. The formal setup represents only a curated abstraction of those inputs; it is not connected directly to flight controls and cannot authorize a launch or command the aircraft.

Decision/claim boundary

The checked object is a proposition about the modeled transition protocol—for example, that a declared loss-of-link transition enters a contingency state without first entering a prohibited mode. Whether the loss detector is calibrated, the containment volume is adequate, the transition is reachable in the deployed binary, or the aircraft is safe to operate remains outside that proposition. Release and operational authority stays with the accountable engineering and flight-operations roles.

Candidate checked statements

Illustrative controlled-English propositions for a future UAS setup include:

  • “Every transition from normal navigation after confirmed command-link loss enters a declared contingency mode.”
  • “No permitted contingency transition commands a waypoint outside the active containment region.”
  • “Pilot override remains permitted in every engaged autonomous flight mode.”

These are candidate schemas, not statements that the current tool or a deployed UAS already implements or proves.

Example architecture

Mission-planning and configuration services export stable identifiers and a versioned assurance view, not raw avionics data. A curator maps them to modes, events, regions, and relations such as mayTransition and overridePermitted. FF Scribe runs off the operational network and records candidates, diagnostics, readings, and decisions. A requirements repository versions accepted propositions; simulation, test, hazard analysis, and approval remain independent evidence channels. A human controls acceptance and requirements changes.

Where verified readback fits

The specialist writes the intended claim in natural language. The system maps it to the mission setup’s scoped proposition hole, and Agda checks syntax, scope, and types. If the checked type is within the configured readback slice, ff-readback produces a finite, audited deterministic family with semantic-rule provenance; unsupported structure fails visibly without a partial reading. The reviewer explicitly accepts the intended reading or supplies feedback for another bounded pass. Compilation alone does not establish an assurance claim.

Potential benefits

This pattern can expose omitted quantifiers, reversed transition direction, accidental overbreadth across modes, and ambiguity between detection and response. The accepted type and deterministic reading create a reviewable link between prose requirements and a formal artifact. Versioned statements can also focus regression reviews: a change to lost-link logic can be assessed against the exact claims whose vocabulary or transition assumptions changed.

Limits/adoption considerations

Type correctness establishes that a proposition is well formed in the chosen setup; it does not establish factual truth, conformance to an airworthiness policy, real-world flight safety, completion of a proof, or fidelity to the author’s intent. Those require, respectively, validated evidence, accountable policy and certification review, system safety engineering and test, proof terms or other verification evidence, and explicit practitioner confirmation. The setup must be governed like an assurance model: terminology, mode semantics, environmental assumptions, and version alignment need named owners. Sensitive mission data should be minimized because natural-language prompts and diagnostic logs can contain operational information.
02Warehouse autonomous-mobile-robot traffic coordination

System/use case

A fleet-engineering review tool for autonomous mobile robots (AMRs) that expresses right-of-way, zone reservation, deadlock recovery, and human-intervention protocols. It targets claims that are usually scattered across fleet-manager configuration, programmable safety-controller logic, commissioning notes, and operational procedures.

Operational setting

In a fulfillment center or factory, robots traverse shared aisles, transfer points, charging bays, and human-access zones. A setup names zones, reservations, robot states, handoffs, and recovery actions. The tool supports design, commissioning, and change review, not real-time collision avoidance.

Decision/claim boundary

The formal claim concerns the abstract coordination protocol—for example, mutual exclusion over a modeled conflict zone or the availability of an escalation transition from a blocked state. It does not determine that localization is accurate, protective fields are correctly configured, braking distance is sufficient, or an installation satisfies a site safety standard. The controls engineer, machinery-safety specialists, and operations owner retain authority over commissioning and operation.

Candidate checked statements

Possible controlled-English propositions include:

  • “If one robot owns a conflict-zone reservation, every other robot is denied entry to that zone.”
  • “Every blocked mission can transition either to a cleared route or to operator assistance.”
  • “A robot in protective stop cannot receive a motion-authorizing dispatch transition.”
  • “Releasing a transfer-point reservation requires completion or cancellation of the associated handoff.”

These illustrate a potential domain setup; they are not deployed fleet rules or current readback coverage claims.

Example architecture

A read-only adapter derives a versioned logical snapshot from fleet configuration and zone maps. A registry names states, zones, reservations, and events. FF Scribe has no command path to robots or the fleet manager. Lifecycle records link accepted propositions to simulations, commissioning tests, and configuration revisions. Replay may test concrete traces but is not an Agda proof. Safety PLCs, onboard functions, and operators remain the active controls.

Where verified readback fits

An engineer describes the coordination property. Setup-scoped translation proposes one Agda type or clarifies ambiguous terms such as “blocked” or “owns.” Agda accepts or rejects the type on formal grounds. If the separate partial readback translation supports that structure, it deterministically renders binders and premises without reordering; otherwise the workflow fails visibly. The engineer confirms robot scope, zone, trigger, and outcomes or gives feedback. The result is a review item, not an enforced control.

Potential benefits

The workflow makes hidden protocol assumptions visible, particularly the distinction between reservation state, physical occupancy, and permission to move. It can give controls, fleet-software, and safety teams a shared artifact for change review. Explicit failed-state and recovery propositions can guide scenario selection for simulation and commissioning, while deterministic readings reduce dependence on model-generated paraphrases during approval.

Limits/adoption considerations

A well-typed mutual-exclusion statement is not evidence that all fleet traces satisfy it. Policy correctness depends on the site’s approved traffic concept; physical safety depends on validated sensing, stopping performance, protective equipment, and human procedures; proof completion requires a proof or exhaustive argument over the relevant model; intent requires explicit engineering acceptance. Vocabulary drift between the setup, vendor state names, and live configuration is a central adoption risk. Teams should also prevent acceptance workflows from becoming a substitute for hazard analysis or validation under representative congestion and failure conditions.
03Automated-driving fallback and minimal-risk transition review

System/use case

A requirements-assurance assistant for an automated-driving stack that formalizes claims about feature engagement, operational-design-domain (ODD) exits, takeover requests, fallback progression, driver override, and transition to a minimal-risk condition.

Operational setting

Systems and safety engineers use the tool during concept development, safety analysis, and software-release impact assessment. A setup defines abstract feature states, ODD status, driver-availability observations, fallback events, degradation classes, and allowed transitions. Logs and scenario catalogs may supply evidence references, but the authoring session does not evaluate perception outputs or actuate the vehicle.

Decision/claim boundary

The proposition describes logical relationships in the approved abstraction, such as which transition must follow a declared ODD exit. It does not decide whether the vehicle is actually outside its ODD, whether a takeover request is timely, whether the minimal-risk maneuver is safe in current traffic, or whether the implementation conforms. Product release remains an accountable human decision supported by safety, test, and compliance evidence.

Candidate checked statements

Potential controlled-English propositions include:

  • “Every confirmed exit from the active operational design domain initiates fallback while the feature is engaged.”
  • “Driver override is permitted from every automated lateral-control state.”
  • “A severe degradation cannot transition directly to normal automated operation without recovery confirmation.”
  • “Every unresolved takeover request progresses to a declared minimal-risk transition.”

They are illustrative formalization targets, not verified properties of any driving system.

Example architecture

A versioned behavioral model remains separate from the production driving stack. Requirements, state-machine definitions, and hazard identifiers feed a curated assurance graph; simulation, track testing, and log analysis attach evidence references. FF Scribe checks a reviewed setup in isolation and returns acceptance records to requirements management. It cannot modify calibration, planning policy, or software. Safety engineers review traceability; release authorities decide lifecycle gates.

Where verified readback fits

The author states a narrow transition or invariant claim in natural language. Translation is constrained to the setup’s explicit state, event, and relation names. Agda rejects malformed applications and scope or type errors; it does not test the feature. The separate ff-readback translation either realizes a supported checked type through its finite, audited family—retaining premise order and scoped entities—or reports unsupported structure without a reading. The safety engineer compares the deterministic readings with the requirement and accepts only the intended one, or gives feedback that starts another bounded proposal-and-check loop.

Potential benefits

The workflow can distinguish an observed condition, declared state, and required response, and makes quantifiers and reachability reviewable. Vocabulary changes can flag accepted propositions for reassessment, connecting change impact to formalized intent and evidence.

Limits/adoption considerations

Type checking does not demonstrate factual correctness of ODD detection, correctness of the selected fallback policy, safe behavior in open traffic, proof of the proposition, or user-intent alignment. Those boundaries require validated sensing and test evidence, governance of the safety concept, vehicle-level verification and validation, proof construction or model checking with stated assumptions, and explicit author confirmation. Temporal and existential claims may exceed the current readback slice and must fail visibly rather than be flattened. Human-factors adequacy and driver-state uncertainty must stay explicit in the safety case.
04Spacecraft onboard autonomy and safing-sequence assurance

System/use case

A protocol-authoring and review system for spacecraft fault protection, covering autonomy rules that isolate a suspect subsystem, preserve power-positive attitudes, inhibit conflicting commands, enter safing, and request ground disposition.

Operational setting

Flight-software, guidance-navigation-and-control, power, and operations specialists use it during procedure development and change control. A mission setup names monitored conditions, autonomy responses, command inhibits, subsystem states, safing milestones, and ground acknowledgements. Simulation and fault injection exercise concrete sequences.

Decision/claim boundary

Checked propositions concern the declared fault-management protocol and its abstract states. They do not establish that telemetry is truthful, thresholds are appropriate, a fault hypothesis is correct, power or thermal margins are adequate, or the flight implementation will execute the modeled path. Mission operations and the responsible engineering authorities decide whether a procedure or build is fit for flight.

Candidate checked statements

Illustrative propositions for a curated mission setup include:

  • “Every confirmed critical power fault transitions either to load shedding or to safing.”
  • “A command inhibited by an active fault response cannot be issued by onboard autonomy.”
  • “Every autonomous safing entry produces a ground-visible notification state.”
  • “Recovery from safing requires both fault-clearance evidence and an authorized recovery event.”

These are proposed statement forms only, not claims about a particular mission or implemented adapter.

Example architecture

A controlled repository holds a versioned fault-response graph with owners for each term. FF Scribe runs on the ground, isolated from commanding, and records the setup, type, check, readings, and decision. An evidence service links accepted propositions to analyses, fault-injection runs, tests, code, and anomaly dispositions. Existing controls protect command authorization; readback never crosses that boundary.

Where verified readback fits

An engineer enters the intended obligation. The model uses only the mission setup and clarifies uncertain conditions, phases, or quantification. Agda checks the type. For a structure supported by the configured profile, ff-readback derives audited deterministic readings while preserving configured constants and premise roles; unsupported structures fail visibly. A qualified practitioner accepts the intended meaning or gives feedback. Confirmation neither approves a flight rule nor uploads a command.

Potential benefits

Formalized, readable claims can help multi-discipline teams review sequences whose hazards arise only after combinations of individually valid responses. They make recovery preconditions, command inhibits, and ground-handoff expectations easier to compare across flight-rule, software, and test baselines. Deterministic readback also supplies a stable human review artifact for anomaly retrospectives and change-control packages.

Limits/adoption considerations

Type correctness is only structural validity inside a setup. Factual telemetry validity, mission-policy correctness, vehicle safety, proof completion, and intended meaning each need separate evidence and authority. The abstraction must represent concurrency, stale observations, timing, and partial failures when they matter; a simple transition graph may otherwise conceal mission-critical behavior. Vocabulary and evidence links require long-lived configuration control. Unsupported temporal or existential constructions must be reported explicitly, and sensitive mission information must be protected in prompts, artifacts, and diagnostic logs.
MLTTDB4 patterns
This application set develops the invariants, protocols, fail states, and boundary-validation themes in the upstream Autonomy domain outline. It is grounded in the current MLTTDB architecture and finite-table profile, not a claim that MLTTDB is an autonomous-system runtime or a certified safety tool. All architectures are illustrative and require review by qualified autonomy, controls, cybersecurity, functional-safety, and operational specialists for the intended system and operating environment.
01Warehouse AMR mission-release policy pack

Operational context

A distribution centre may run heterogeneous autonomous mobile robots (AMRs) under a warehouse execution system (WES) and fleet manager. Mission release depends on vehicle capability, payload class, aisle direction, pedestrian-zone status, lift or door interfaces, battery reserve, and recovery policy. These constraints are often distributed across map annotations, fleet parameters, commissioning documents, and WES rules. A bad configuration release can permit an infeasible route class, omit a required hand-off, or assign a recovery mode that conflicts with a zone’s access policy.

Why MLTTDB fits

The assurance target is a bounded configuration baseline, not live traffic control. Tables can represent mission classes, robot capabilities, zone policies, allowed transitions, and exception responses. Proof definitions can state that every releasable mission has compatible payload and locomotion capabilities, that entry to a controlled zone has a defined authorization and exit, and that every modeled degraded state terminates in a permitted recovery or human-assistance state. Stable UUIDs are useful when policy rows are edited or reordered while external release records retain identity.

Example architecture

WES/map/fleet exports -> reconciliation + review -> MLTTDB term store
                                                     |
proof-owned schema + invariants ---------------------+
                                                     v
                                           Agda/Lean/Rocq check
                                                     |
                                      signed release report + bundle
                                                     v
                                      fleet-manager deployment pipeline

An external adapter normalizes approved WES mission templates, map-zone identifiers, and vendor capability codes into reviewed source-language records. The term store preserves their order, UUIDs, and metadata. A proof-assistant module supplies the domain model and release predicates; CI or the store’s verification endpoint invokes the compatible checker. A separate deployment pipeline correlates the successful report with exact source exports and the fleet-manager bundle.

Representative typed artifacts

  • RobotProfile, including drive envelope, payload interface, and supported stop or recovery modes.
  • ZonePolicy, with access class, required interface handshake, and permitted mission states.
  • MissionTemplate, referencing a route class, payload class, and required recovery policy; Agda rows may use finite UUID lookup for controlled references to earlier tables.
  • TransitionRule and FailStateDisposition, separating normal progression from blocked, degraded, and manual-recovery outcomes.
  • A ReleaseManifest aggregate term, reconciled to the exported row UUIDs, carrying a Releasable witness or decidable check over the complete approved pack represented by that term.

Checks and evidence

Checks can cover reference closure, unique ownership of zone permissions, capability compatibility, absence of unsupported state transitions, recovery coverage, and declaration-order/acyclicity requirements for Agda table dependencies. Negative fixtures should include unknown policy references, missions with insufficient capability, missing degraded-state dispositions, and transition cycles forbidden by the formal model. Evidence should retain the checker version, proof source revision, database snapshot identifier, ordered record UUIDs, generated source where applicable, process output, and the deployment bundle digest. This is reproducible release evidence, not an immutable audit facility supplied by MLTTDB itself.

Potential benefits

The approach can expose configuration interactions before commissioning, replace spreadsheet joins with typed references, and make operational assumptions reviewable by controls and warehouse engineers. It can also make fleet or map upgrades easier to compare: unchanged policy identities remain stable, while failed proofs localize which modeled obligation no longer holds.

Deployment boundary

The fleet manager, safety-rated protective devices, traffic arbitration, localization, braking, and human exclusion controls remain authoritative at runtime. MLTTDB does not ingest telemetry, reserve routes, release missions, or guarantee collision avoidance. Deployment requires site acceptance testing, vendor-supported configuration controls, cybersecurity review, and qualified safety assessment of both the formalization and the physical installation.
02BVLOS inspection-drone contingency-envelope release

Operational context

A beyond-visual-line-of-sight inspection operation coordinates aircraft, payload, command-and-control (C2) links, navigation services, weather sources, ground risk controls, and remote-pilot procedures. Before a mission profile is made available, the operator must reconcile aircraft configuration with route segments and contingency responses for degraded navigation, loss of C2, energy shortfall, geofence approach, payload fault, or unavailable recovery sites. The relevant envelope varies by aircraft and approved concept of operations; it should not be inferred from generic rules.

Why MLTTDB fits

MLTTDB can check a finite, reviewed mission-policy pack at configuration release. Tables can encode aircraft capability profiles, route-segment classes, recovery sites, trigger categories, and contingency procedures. The proof module can require that each modeled trigger in each flight phase maps to an authorized response, that a response’s prerequisites are compatible with the aircraft and segment, and that escalation never silently returns to nominal autonomy. This use exploits typed, ordered records without pretending that a static model captures live airspace or meteorology.

Example architecture

approved ConOps + aircraft config + route design
                    |
                    v
        domain adapter and accountable review
                    |
       MLTTDB policy/configuration database <--- proof-owned flight model
                    |
        project CI invokes proof assistant
                    |
     assurance dossier + approved profile digest
                    v
          operations planning platform

The adapter resolves identifiers from configuration management, route design, and procedure repositories and produces a candidate baseline. MLTTDB stores proof-language rows; the proof assistant checks their modeled relationships. An assurance service packages results with the exact flight-profile digest. The operations platform accepts only a separately authorized baseline and performs its own current-data and authorization checks.

Representative typed artifacts

  • AircraftConfiguration, capturing approved propulsion, navigation, C2, and recovery capabilities as abstract capabilities rather than raw telemetry.
  • FlightPhase and SegmentEnvelope, with permitted modes and declared operational assumptions.
  • ContingencyTrigger, RequiredResponse, and EscalationTarget records.
  • RecoverySiteCapability linked to applicable segment and aircraft classes.
  • A ContingencyCoverageManifest aggregate term, externally built and reconciled to the profile export, enumerating the phase-trigger pairs, responses, recovery sites, and row UUIDs covered by release checks.
  • Proof obligations such as trigger coverage, response precondition satisfaction, monotone escalation, and no modeled path to an unhandled terminal state.

Checks and evidence

A release suite can test that all referenced recovery sites and response procedures exist, every phase-trigger pair has exactly the intended coverage, energy or navigation-dependent responses declare their prerequisites, and no contingency path depends on a later or cyclic definition. Scenario fixtures should exercise loss-of-link during multiple phases, a recovery site withdrawn from the baseline, conflicting response priority, and an aircraft variant missing a required capability. Evidence includes proof/checker revisions, accepted and rejected fixtures, ordered row identity, source export hashes, and the reviewed assumptions attached to the mission-profile version.

Potential benefits

Typed contingency packs can reveal coverage gaps and variant drift earlier than simulator or flight-test execution, while giving remote pilots and safety assessors a precise inventory of modeled responses. Stable identities also support impact analysis when one recovery site, aircraft configuration, or procedure changes. The proof artifact can complement simulation by showing exhaustive coverage over the finite modeled categories.

Deployment boundary

MLTTDB neither obtains current weather or airspace data nor authorizes BVLOS operations, computes flight trajectories, commands the aircraft, or executes contingencies. Those duties stay with approved operational systems and accountable personnel. Regulatory interpretation, airworthiness, operational authorization, human-factors assessment, simulation, and flight testing must be performed by qualified specialists for the applicable jurisdiction and operation.
03Industrial robotic-cell changeover interlock baseline

Operational context

A flexible manufacturing cell may combine robots, positioners, tooling, conveyors, machine vision, process equipment, and safety PLC functions. Product changeover selects recipes, tools, safe positions, guarding modes, and handshake sequences. Controls engineers need assurance that an approved changeover baseline does not enable a process step before the required tool, fixture, zone-clear, and equipment-ready conditions are established, and that aborted changeovers have defined recovery states.

Why MLTTDB fits

The finite object is the controlled recipe/interlock catalogue released to the cell, not the PLC scan-cycle state. MLTTDB tables can carry equipment profiles, recipe phases, permissive groups, handshake contracts, and recovery plans. An external release compiler also emits a CellBaselineManifest aggregate term and reconciles its UUID list and digest with the table export. Proofs over that term can establish structural properties across the represented catalogue: required interlocks precede hazardous commands in the abstract sequence; mutually exclusive modes are never demanded together; every abort state has a manual or automatic recovery disposition; and each recipe uses tooling rated for the modeled operation class.

Example architecture

PLM/MES recipe + PLC interface dictionaries + safety design
                          |
                controlled reconciliation
                          v
                MLTTDB candidate baseline
                          |
              proof assistant verification
                          v
         change-control evidence and codegen inputs
                          |
             PLC/robot offline validation -> site release

Engineering adapters map PLM recipe identifiers, MES product variants, and controls tags to a reviewed vocabulary. MLTTDB stores the resulting typed source rows and can orchestrate their verification. A separate generator may consume an accepted baseline, but its output is independently reviewed, compiled, simulated, and commissioned against the actual PLC and robot programs. No proof-language record is sent directly to an actuator.

Representative typed artifacts

  • EquipmentCapability and ToolingCompatibility catalogues.
  • RecipePhase with abstract entry conditions, commanded operation class, and completion indication.
  • PermissiveGroup, distinguishing process permissives from safety-rated protective functions.
  • HandshakeContract for producer/consumer request, acknowledge, timeout, and abort states.
  • RecoveryPlan and proofs of phase sequencing, interlock coverage, exclusive mode selection, and recovery completeness.

Checks and evidence

Checks should reject dangling equipment references, unsupported recipe/tool pairs, contradictory mode demands, missing timeout outcomes, commands without modeled prerequisites, and recovery graphs that cycle without an approved operator intervention state. Test baselines can model loss of a ready signal, tool-identification mismatch, partial changeover, and an obsolete device profile. Review evidence ties checker output and generated definitions to the recipe revision, safety-requirements revision, software build, and offline simulation campaign. The formal model should make explicit which PLC timing, diagnostic, and failure assumptions it abstracts away.

Potential benefits

This separates cross-equipment consistency checking from vendor-specific implementation syntax, allowing automation, manufacturing, and safety engineers to review one typed baseline. It may reduce late discovery of variant-specific omissions, improve traceability from a permissive to the recipes that depend on it, and make change impact visible when tooling or interface contracts are revised.

Deployment boundary

Safety PLC logic, emergency stopping, protective devices, drive safety functions, lockout/tagout procedures, and validated robot programs remain the real safeguards. MLTTDB is not a safety controller, does not monitor I/O, and does not certify generated PLC or robot code. A release still needs the applicable machinery risk assessment, functional-safety lifecycle activities, offline and on-cell testing, configuration control, and authorized sign-off.
04Tool-using AI agent protocol-assurance service

Operational context

An enterprise AI agent may call search, ticketing, code, messaging, or data tools across multi-step tasks. Its orchestration policy must constrain which agent role can invoke which tool, what data classification is permitted, whether human approval is required, and how failures, retries, and compensating actions behave. Prompt-only descriptions are difficult to audit, especially when a new tool or workflow introduces an action path that bypasses an approval boundary.

Why MLTTDB fits

The policy catalogue is finite and changes under release control. Row types can represent roles, tool capabilities, protocol states, approval requirements, data classes, and failure dispositions. Proofs can check that every executable transition has an authorization basis, privileged effects require the modeled approval state, terminal failures cannot silently resume, and compensating actions exist for modeled partially completed operations. Here MLTTDB can support both release-time catalogue checks and an internal verification service for proposed workflow definitions; it is not the runtime policy decision point.

Example architecture

tool registry + IAM policy + workflow definitions
                       |
             normalization and owner review
                       v
             MLTTDB protocol catalogue <--- proof-owned state model
                       |
             verification API / release CI
                       v
             approved policy-bundle digest
                       |
       agent orchestrator + runtime policy engine + audit pipeline

External connectors reconcile canonical tool, principal, and data-class identifiers. The term store retains reviewed proof-language policy records, while the proof assistant evaluates protocol invariants. CI publishes a result bound to the proposed bundle. The orchestrator and policy engine load only a separately authorized bundle and enforce decisions using authenticated runtime context; an observability pipeline records actual actions.

Representative typed artifacts

  • PrincipalRole, ToolCapability, and EffectClass, including read, mutation, external communication, and irreversible-effect distinctions.
  • ProtocolState and Transition, with initiator, preconditions, effect, next state, and failure state.
  • ApprovalRequirement and DelegationScope, tied to an external IAM policy identity rather than invented by the agent.
  • CompensationContract for operations whose effects can be reversed or explicitly cannot be reversed.
  • A ProtocolBundleManifest aggregate term, reconciled to the tool registry, IAM-policy snapshot, and exported row UUIDs, materializing the transition graph used for bundle-wide reachability and privilege checks.
  • Proofs of least modeled privilege, approval-before-effect, failure closure, and absence of forbidden state paths.

Checks and evidence

Verification can reject unknown tool references, privilege escalation through delegation, an external side effect reachable before approval, retries of an operation classified as non-idempotent without a disposition, and failure states with outbound privileged transitions. Counterexample fixtures should cover confused-deputy paths, stale approval, tool substitution, partial completion, and compensation failure. Evidence links the checked row UUIDs, proof source, checker output, IAM/tool-registry snapshots, workflow-bundle digest, and reviewer approvals. Actual runtime traces must be captured and reconciled elsewhere.

Potential benefits

The typed protocol catalogue gives security, platform, and workflow owners a shared object for reviewing authorization and failure behavior. Exhaustive checks over modeled states can find rare multi-step bypasses that per-tool unit tests miss, and stable row identities improve impact analysis as tools and approval policies evolve. The same evidence can gate rollout of a workflow variant without coupling the policy model to one agent framework.

Deployment boundary

MLTTDB does not authenticate principals, inspect prompts, prevent prompt injection, authorize a live call, execute compensation, or provide an immutable action log. Runtime IAM, policy enforcement, sandboxing, secrets management, egress controls, human approval UX, and incident response remain mandatory. Security and safety specialists must review whether the modeled states and effects faithfully cover each concrete tool integration.
State Machine Studio3 demos
SMAgentic Change Executor

This example represents an autonomous agent carrying out a production infrastructure change under bounded authority. It separates a requested outcome from the plan, approval, execution capability, rollout observations, and final acceptance. That separation is essential when an agent can call deployment, configuration, identity, or cloud-management tools: an apparently reasonable objective must not become permission to alter unspecified resources.

The normal campaign begins by parsing the desired outcome, prohibited effects, target resources, dependency boundaries, success measures, and rollback conditions. The proposed sequence of tool calls is exercised against a read-only snapshot, checked for permissions and resource invariants, and revised if targets or ordering are ambiguous. Authorization is then bound to the verified plan digest and expressed through scoped, expiring capabilities. Execution proceeds in bounded batches, with health signals, invariant checks, checkpoints, and observations recorded after each batch. Outcome verification compares the observed environment with success criteria, probes dependencies for regressions, and assembles a trace from intent to result. Only a verified outcome closes as accepted.

The machine makes failure containment explicit. An invalid simulation returns for replanning before authority is issued. A breached invariant during rollout, or a regression found during outcome verification, enters rollback recovery. Unused capabilities are revoked, the latest verified checkpoint is restored, and recovery invariants are checked. The campaign may return for reauthorization and resume, or close after a verified rollback. These controls matter to platform engineering and change-management teams because they limit blast radius, prevent approval drift after a plan changes, and preserve evidence that the actions actually performed were the actions reviewed.

Layer 1 — Change campaign stages

This layer is the campaign view for a service owner, change manager, or incident commander. It shows proposal, verification, authorization, execution, outcome review, rollback, and closure, including the only permitted routes back to an earlier stage. It intentionally hides individual tool calls so governance reviewers can focus on authority, acceptance, and recovery boundaries.

Layer 2 — Authorization and rollout protocols

This layer describes the operating procedures that make autonomous change safe: defining prohibited effects, simulating against a snapshot, binding approval to a digest, issuing short-lived capabilities, batching rollout, checkpointing, probing dependencies, and validating recovery. It is suitable for runbooks, policy-as-code reviews, and control design. Provider-specific API payloads and command syntax are outside this layer.

Layer 3 — Tool-level actions

This layer exposes the concrete actions and observations performed by the agent, such as identifying resources, checking permission scope, applying an approved batch, monitoring health, revoking unused credentials, restoring a checkpoint, and retaining the execution trace. It supports dry-run tests and forensic replay. It deliberately excludes internal model reasoning and vendor-specific tool implementations; the safety contract is defined by observable calls, results, and enforced boundaries.
Open interactive model
SMInspection Drone Operation

This example describes an unmanned inspection sortie from planning through evidence closure. The aircraft must collect usable sensor data while staying inside approved airspace, standoff, altitude, weather, control-link, and energy limits. The machine frames those limits as operational protocols rather than relying on the autopilot to make an unconstrained best effort.

The planned path begins with waypoints and inspection objectives, together with the applicable airspace, daylight, weather, and site constraints. Launch clearance verifies the command link, return-position fix, battery reserve, geofence, and approved flight plan before arming. The aircraft then follows its authorized altitude corridor to the asset, continuously tracking link quality, traffic, obstacles, and remaining energy. On station it stabilizes at each viewpoint, acquires the required imagery or measurements, checks data quality, and maintains its prescribed standoff. A planned return selects a route that fits the current energy margin, verifies that the landing zone is clear, and ends with touchdown and disarm confirmation. Closure reconciles the collected dataset against the inspection plan.

An aircraft is never assumed to continue simply because it is airborne. A rejected clearance returns the sortie for replanning, while cancellation before launch can close it without flight. Transit and inspection anomalies enter a common emergency response where link loss, worsening weather, navigation error, traffic conflict, or low energy is classified. Depending on the remaining safety envelope, the response can hold, return, divert, land, or resume the inspection after bounded recovery. The autonomous decision and any remote-pilot intervention are retained. These controls matter to UAS operators because a valid inspection objective does not override airspace authorization or safe recovery, and because flight logs must explain why the aircraft deviated from the original plan.

Layer 1 — Flight operation phases

This layer gives the remote pilot, mission commander, or operations manager the sortie-level picture: planning, clearance, outbound transit, inspection, return, emergency response, and closure. It highlights when authority changes and where an operation may be aborted or recovered. It intentionally omits waypoint commands and individual sensor checks so the overall flight disposition remains readable.

Layer 2 — Airborne safety protocols

This layer describes the procedures used within each phase: checking geofence and reserve before launch, monitoring link and traffic in transit, maintaining standoff on station, and choosing hold, return, diversion, or landing during an anomaly. It contains the operational decision points expected in a flight manual or safety case. It excludes low-level stabilization mathematics and raw telemetry streams.

Layer 3 — Autopilot actions

This layer shows the executable observations and actions behind the protocols, including loading constraints, arming the cleared plan, climbing within the corridor, avoiding detected obstacles, quality-checking captures, selecting an energy-feasible return path, and recording fail-state decisions. It supports simulation and test coverage. Airframe-specific control loops, radio packets, and sensor-driver behavior are intentionally left to the deployed autopilot implementation.
Open interactive model
SMAutonomous Warehouse Fulfillment

This example represents a robotic pick-and-deliver mission in a shared warehouse. It treats the mission as more than motion between two coordinates: inventory custody, aisle reservations, payload limits, separation from people and equipment, and battery reserve must remain valid from dispatch through confirmed handoff. The machine therefore makes the operational authority given to the robot explicit and bounded.

The normal path starts when the warehouse control system validates a pick task, destination slot, robot allocation, and payload assignment. Route authorization then checks aisle geofences, traffic reservations, load limits, and energy margin before issuing an approved route envelope. During autonomous execution the robot localizes against the current map, navigates the reserved segments, responds to obstacles, and secures the requested unit. At the destination, handoff verification scans both payload and location identifiers and waits for inventory acknowledgement before closing the mission and reconciling the stock movement.

The return paths are as important as the happy path. An infeasible route goes back for task revision rather than being dispatched. A route, grasp, proximity, or low-energy fault moves execution into a safe-stop recovery state while payload custody is preserved. A mismatched destination or inventory scan is quarantined instead of being accepted as delivery. Recovery can lead to a newly authorized route, a supervised handoff, or closure as an unrecoverable mission. These controls matter because a locally plausible robot action can still violate fleet traffic rules, lose chain of custody, or create an inventory discrepancy. Recording invariant checks and operator interventions also gives operations and safety teams a usable incident trail.

Layer 1 — Mission lifecycle

This layer is the view a fulfillment operations lead would use to follow the job from mission request through route authorization, autonomous execution, handoff, recovery, and closure. It shows the major custody and accountability boundaries and the permitted loops between them. It intentionally excludes individual map updates, scans, and actuator commands so a reviewer can see whether the mission followed an authorized operational path without controller-level noise.

Layer 2 — Robot operating procedures

This layer expands each lifecycle state into the procedures carried out by the warehouse control system, fleet manager, robot, and operator. It includes task and slot validation, reservation checks, safe-stop classification, supervised recovery, and inventory reconciliation. It is the right scope for runbooks and exception handling. It does not model individual sensor samples or motor-control cycles; those details are summarized as procedure outcomes and invariant checks.

Layer 3 — Controller actions

This layer exposes the concrete actions that produce each procedural result: acquiring a local map, tracking obstacles, securing the unit, scanning identifiers, retaining the payload during a stop, and archiving intervention evidence. It is useful for controls engineering, test design, and trace reconstruction. Continuous control laws, vendor-specific message formats, and raw telemetry are deliberately outside the example; they can be attached beneath these actions in an implementation-specific model.
Open interactive model
Explore patternsReview product applications

Cabinet index

Explore Formal Foundry

Search the archive

Find a page

Type to search the published content.