Verified Digital Agents (VDA) Tools API

openapi: 3.2.0
info:
  title: HITL — human decisions on agent actions Tools API
  version: 0.1.0
  description: The getvda.ai substrate that owns human decisions on agent actions. External callers (ACP, onboard-agent) register an authority config, then raise → resolve → sealed hitl_decision. Discovery is public; tool calls require Contract A (a Witness Bearer). A NEW caller is created only by controller-signed genesis; register_authority_config updates an existing caller. See docs/EXTERNAL-CALLERS.md.
  x-git-sha: d347a708f292368e6656381ca9e2ed983260657b
servers:
- url: https://hitl.getvda.ai
security:
- bearerAuth: []
tags:
- name: Tools
paths:
  /v1/tools:
    get:
      operationId: list_tools
      summary: List the tool surface (names + schemas)
      responses:
        '200':
          description: tools
      tags:
      - Tools
  /v1/tools/raise_hitl_item:
    post:
      operationId: raise_hitl_item
      summary: Raise a decision for human review
      description: Raise an item for a human to decide. HITL routes it to an authorised band using YOUR registered authority config — it never infers a band and never defaults one. Returns remaining quota so you can self-limit rather than discovering a ceiling by hitting it.
      x-mutating: true
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - caller_id
              - decision_ref
              - decision_class
              - escalation_label
              - statement
              - basis_captured_at
              - governing_clauses
              properties:
                caller_id:
                  type: string
                  description: Your registered caller id.
                decision_ref:
                  type: string
                  description: Your idempotency key. Re-raising the same decision_ref is rejected, so a retry cannot create a duplicate item.
                decision_class:
                  type: string
                  description: The kind of decision. Must be in your registered permitted_decision_classes.
                escalation_label:
                  type: string
                  description: A label from your registered authority config. HITL maps it to a band. An unknown label is an ERROR, not a default — a defaulted band is a silent decision about who may decide.
                statement:
                  type: string
                  description: What is being asked, in plain language.
                proposed_action:
                  type: string
                  description: What the agent recommends.
                basis_captured_at:
                  type: string
                  description: 'ISO-8601. When the DECIDING SYSTEM SAW ITS EVIDENCE — not when you called HITL. This is load-bearing: it is what the decider saw at recommendation time.'
                governing_clauses:
                  type: array
                  minItems: 1
                  description: 'Governing clauses in force at decision time. At least one is required. Capture `text` as well as `ref`: policies drift, and the record must show what the clause SAID when it was applied.'
                  items:
                    type: object
                    required:
                    - ref
                    properties:
                      ref:
                        type: string
                        description: Policy / SOP / rule identifier.
                      text:
                        type: string
                        description: The clause text as it read at decision time.
                      hash:
                        type: string
                        description: sha256:<64 hex> of the policy source version.
                evidence:
                  type: array
                  description: Content addresses ONLY — a reference and a digest. HITL has no field anywhere that can hold content, so the PII-bearing original never leaves your deployment. Supply this OR evidence_omitted_reason, never both.
                  items:
                    type: object
                    required:
                    - ref
                    - hash
                    properties:
                      ref:
                        type: string
                        description: URI, id, or a Witness recordId.
                      hash:
                        type: string
                        pattern: ^sha256:[0-9a-f]{64}$
                        description: sha256:<64 hex>.
                      media_type:
                        type: string
                        description: Optional media type.
                      descriptor:
                        type: string
                        description: Short NON-PII label, max 200 chars. A label, not a payload.
                      captured_at:
                        type: string
                        description: ISO-8601 capture time.
                evidence_omitted_reason:
                  type: string
                  description: REQUIRED if evidence is empty. State plainly why there is none. Never synthesise a placeholder that looks like evidence — an unavailable source must be representable as unavailable, not as a plausible object.
                domain_ref:
                  type: string
                  description: A correlation handle into YOUR store, so you can re-render the rich card. Not a payload — HITL never interprets it and it must not carry PII.
                descriptors:
                  type: object
                  description: Small non-PII key/value labels for list views. Capped at 4KB.
              additionalProperties: false
      responses:
        '200':
          description: raise_hitl_item result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/list_hitl_items:
    post:
      operationId: list_hitl_items
      summary: List decision items
      description: List item summaries. Summaries deliberately carry NO evidence, statement, or domain_ref — use get_hitl_item for a single item when you need detail.
      x-mutating: false
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                caller_id:
                  type: string
                  description: Filter to one caller.
                status:
                  type: string
                  enum:
                  - open
                  - resolved
                  - cancelled
                band:
                  type: string
                  description: Filter to an authority band.
                since:
                  type: string
                  description: ISO-8601 lower bound on created_at.
              additionalProperties: false
      responses:
        '200':
          description: list_hitl_items result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/get_hitl_item:
    post:
      operationId: get_hitl_item
      summary: Get one decision item
      description: Full item including evidence content-addresses and, once resolved, the outcome, the asserted actor, and the seal record id. Note the resolution reports the asserted actor and the authenticated calling account separately — they are different facts.
      x-mutating: false
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - item_id
              properties:
                item_id:
                  type: string
                  description: The item id.
              additionalProperties: false
      responses:
        '200':
          description: get_hitl_item result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/resolve_hitl_item:
    post:
      operationId: resolve_hitl_item
      summary: Record a human decision
      description: Record the outcome of a human decision and seal it. The seal is durably queued before this returns and never blocks you — if Witness is unavailable the result reports seal.status "pending" and the outbox completes it. `escalate` creates the next-band item by walking your registered ladder. `baseline` requires authority to WIDEN a ceiling, which is a different thing from authority to decide the instance.
      x-mutating: true
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - item_id
              - outcome
              - actor
              - statement
              - resolved_by_account
              properties:
                item_id:
                  type: string
                  description: The item id.
                outcome:
                  type: string
                  enum:
                  - approve
                  - deny
                  - escalate
                  - baseline
                  description: One vocabulary. There are exactly four outcomes.
                actor:
                  type: object
                  required:
                  - id
                  description: The deciding human, AS ASSERTED BY YOUR SURFACE. HITL records this; it does not authenticate it.
                  properties:
                    id:
                      type: string
                      description: Identifier.
                    role:
                      type: string
                      description: The authority under which they decided.
                statement:
                  type: string
                  description: The decision and its rationale.
                resolved_by_account:
                  type: string
                  description: The authenticated account submitting this resolution. Recorded separately from the asserted actor on purpose.
                baseline:
                  type: object
                  required:
                  - bounds
                  - scope
                  description: Required when outcome is "baseline". Both bounds and scope must NAME their kind — an unbounded grant must say {"kind":"unbounded"} explicitly. A missing field never grants permission.
                  properties:
                    bounds:
                      type: object
                      description: One of {"kind":"unbounded"} | {"kind":"numeric","unit":...,"max":...} | {"kind":"enum","values":[...]}. Units are compared exactly and never coerced.
                    scope:
                      type: object
                      description: One of {"kind":"any"} | {"kind":"qualified","qualifiers":{...}}.
              additionalProperties: false
      responses:
        '200':
          description: resolve_hitl_item result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/list_baselines:
    post:
      operationId: list_baselines
      summary: List baselines
      description: Active baselines for a caller, with unbounded_count surfaced separately. An unbounded baseline is the widest grant a customer can make, so it is flagged explicitly rather than left to be inferred from the shape of bounds.
      x-mutating: false
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - caller_id
              properties:
                caller_id:
                  type: string
                  description: The caller id.
                include_revoked:
                  type: boolean
                  description: Include revoked baselines.
              additionalProperties: false
      responses:
        '200':
          description: list_baselines result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/revoke_baseline:
    post:
      operationId: revoke_baseline
      summary: Revoke a baseline
      description: Revoke a baseline and seal the revocation. Never a delete — the row and its trail remain, because accumulated baselines are exactly what an auditor needs to review.
      x-mutating: true
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - baseline_id
              - revoked_by
              - reason
              - caller_id
              properties:
                baseline_id:
                  type: string
                  description: The baseline id.
                revoked_by:
                  type: string
                  description: Who revoked it.
                reason:
                  type: string
                  description: Why. Required — a revocation with no reason is not evidence.
                caller_id:
                  type: string
                  description: The caller id.
              additionalProperties: false
      responses:
        '200':
          description: revoke_baseline result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/match_baseline:
    post:
      operationId: match_baseline
      summary: Check baseline containment
      description: 'Parity check for your local read-model. This is NOT the hot path: match locally in your own decision loop so you take no HITL latency or availability dependency. Use this to verify your projection agrees with the system of record.'
      x-mutating: false
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - caller_id
              - request
              properties:
                caller_id:
                  type: string
                  description: The caller id.
                request:
                  type: object
                  required:
                  - decisionClass
                  properties:
                    decisionClass:
                      type: string
                      description: Decision class.
                    value:
                      description: Number or string, per the bounds kind.
                    unit:
                      type: string
                      description: Required for numeric bounds. A missing unit is a mismatch, never a wildcard.
                    qualifiers:
                      type: object
                      description: Scope qualifiers.
              additionalProperties: false
      responses:
        '200':
          description: match_baseline result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/register_authority_config:
    post:
      operationId: register_authority_config
      summary: Register an activated authority config
      description: Register the authority config that governance has ACTIVATED. HITL never authors governance — git is the system of record and this is a projection of it. Every non-genesis registration must carry git_commit and the activation seal, so registration can never become a route around the governance pipeline.
      x-mutating: true
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - caller_id
              - bands
              - label_to_band
              - roster
              - permitted_decision_classes
              - max_raises_per_hour
              - max_open_items
              - git_commit
              - activation_seal_record_id
              properties:
                caller_id:
                  type: string
                  description: The caller id.
                bands:
                  type: array
                  items:
                    type: string
                  description: The authority ladder, ordered narrowest first, widest last. Order IS the escalation path.
                label_to_band:
                  type: object
                  description: escalation_label -> band. Every band named must exist in the ladder.
                roster:
                  type: object
                  description: 'band -> [actor ids]. Bands NEST: an actor on a wider band may decide narrower items.'
                permitted_decision_classes:
                  type: array
                  items:
                    type: string
                  description: The classes this caller may raise.
                max_raises_per_hour:
                  type: integer
                  minimum: 1
                max_open_items:
                  type: integer
                  minimum: 1
                git_commit:
                  type: string
                  description: The commit this config was activated from.
                activation_seal_record_id:
                  type: string
                  description: The Witness attestation that activated it.
              additionalProperties: false
      responses:
        '200':
          description: register_authority_config result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
  /v1/tools/get_raise_quota:
    post:
      operationId: get_raise_quota
      summary: Check remaining raise quota
      description: Remaining raises this hour, remaining open-item headroom, and your permitted decision classes. Read-only — checking does not consume quota.
      x-mutating: false
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - caller_id
              properties:
                caller_id:
                  type: string
                  description: The caller id.
              additionalProperties: false
      responses:
        '200':
          description: get_raise_quota result
          content:
            application/json: {}
        '400':
          $ref: '#/components/responses/DomainError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/AuthorityError'
        '409':
          $ref: '#/components/responses/QuotaOrConstraint'
      tags:
      - Tools
components:
  responses:
    AuthorityError:
      description: unknown_escalation_label | actor_not_on_roster | actor_cannot_widen_ceiling | decision_class_not_permitted
    QuotaOrConstraint:
      description: quota_exceeded (typed, not a bare 429) | a store constraint (e.g. caller_not_found, items_decision_ref_uq)
    DomainError:
      description: a typed lifecycle/validation error (e.g. evidence_or_reason_required)
    Unauthorized:
      description: missing/invalid Witness Bearer (Contract A)
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'Contract A: a Witness Bearer (wtn.<keyId>.<secret>) validated by HITL via Witness GET /whoami. Authorization header only. This authenticates the CALLING account; the human decider on a resolution is asserted separately and never authenticated by HITL.'