> ## Documentation Index
> Fetch the complete documentation index at: https://docs.paywithlocus.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Describe one selected tool

> Returns the full input schema, example, response contract, pricing, and next action for one principal-visible search result. Secret keys require tenant:read. This operation does not call a provider or burn credits.



## OpenAPI

````yaml /api-reference/openapi.json post /credits/tools/describe
openapi: 3.1.0
info:
  title: Locus Pro API
  description: >-
    Access paid tools, manage prepaid balances, and build usage billing. Send
    money as exact decimal strings and reuse Idempotency-Key on retries.
    Management routes require a scoped server key or authorized dashboard
    session. Sensitive workspace changes require an owner or admin with recent
    MFA or passkey verification, except where an operation documents a stricter
    boundary. Interactive agents use MCP OAuth; unattended agents use scoped
    Agent Connections. Browser widgets use end-user tokens.
  version: 0.7.0
servers:
  - url: https://api.paywithlocus.com/api
    description: Production
  - url: https://api.stage.paywithlocus.com/api
    description: Stage — evaluation and integration testing
security:
  - secretKey: []
tags:
  - name: Authentication
    description: Email-verified self-serve account creation and dashboard identity
  - name: Tenants
    description: Tenant profile, keys, and settings (dashboard session or secret key)
  - name: Workspace members
    description: Invite-only human workspace membership and role administration
  - name: Catalog
    description: Enable/disable APIs and set markups
  - name: Custom APIs
    description: Feature-gated enterprise BYOK providers and schema-backed custom actions
  - name: End users
    description: End-user accounts, tokens, and allocations
  - name: Top-ups
    description: Locus-hosted checkout top-ups and quotes
  - name: Ledger
    description: Burn/top-up history and earnings
  - name: Webhooks
    description: Signed events, delivery inspection, and replay
  - name: Burn
    description: Metered pay-per-use calls
  - name: MCP
    description: Stateless Streamable HTTP transport and MCP tool-result contracts
  - name: Okibi Identity
    description: >-
      Feature-gated Okibi identity verification and scoped native CLI credential
      bootstrap
  - name: Widget
    description: End-user JWT surface; a matching publishable key is optional
  - name: Agent-native onboarding
    description: >-
      Self-registration, human Stripe funding handoff, and restricted account
      setup for headless agents
  - name: Hosted Workflows
    description: >-
      Tenant-private TypeScript Workflow definitions, immutable versions,
      bounded runs, artifacts, and recovery
  - name: Agent connections
    description: Scoped, expiring, revocable credentials for agent execution
  - name: Recipes
    description: >-
      Search, research, extraction, enrichment, and travel outcomes across
      providers
paths:
  /credits/tools/describe:
    post:
      tags:
        - Catalog
      summary: Describe one selected tool
      description: >-
        Returns the full input schema, example, response contract, pricing, and
        next action for one principal-visible search result. Secret keys require
        tenant:read. This operation does not call a provider or burn credits.
      parameters:
        - $ref: '#/components/parameters/SessionBindingHeader'
        - name: X-Locus-End-User
          in: header
          required: false
          schema:
            $ref: '#/components/schemas/ExternalUserId'
          description: Optional end-user identity for a tenant secret key.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
                - slug
              properties:
                slug:
                  type: string
                  pattern: ^[A-Za-z0-9][A-Za-z0-9._-]*/[A-Za-z0-9][A-Za-z0-9._-]*$
                operation_query:
                  type: string
                  maxLength: 256
                  description: >-
                    Original search intent used to select the most relevant
                    operation from a directory endpoint.
              additionalProperties: false
      responses:
        '200':
          description: Full selected tool contract
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ToolDescribeResponse'
        '400':
          description: Invalid slug
        '401':
          description: Missing or invalid discovery credential
        '404':
          description: Tool is not visible to this principal
        '500':
          description: Tool description failed
      security:
        - secretKey: []
        - sandboxKey: []
        - endUserToken: []
        - agentConnection: []
components:
  parameters:
    SessionBindingHeader:
      name: X-Locus-Session-Id
      in: header
      required: false
      schema:
        type: string
        minLength: 16
        maxLength: 128
        pattern: ^[A-Za-z0-9][A-Za-z0-9._:-]{15,127}$
      description: >-
        Required only when the end-user JWT carries sid. Send the original
        high-entropy session value; sid is its SHA-256 fingerprint. Ignored for
        secret-key authentication.
  schemas:
    ExternalUserId:
      type: string
      minLength: 1
      maxLength: 200
      pattern: ^[A-Za-z0-9][A-Za-z0-9._:@/-]{0,199}$
      description: >-
        Case-sensitive immutable ID in the tenant namespace. Prefer an
        identity-provider subject, not an email address.
    ToolDescribeResponse:
      type: object
      required:
        - success
        - tool
      properties:
        success:
          const: true
        tool:
          type: object
          required:
            - slug
            - tool
            - provider
            - endpoint
            - title
            - enabled
            - description
            - contract_revision
            - contract_digest
            - pricing
            - method
            - path
            - inputSchema
            - exampleArguments
            - annotations
            - next_step
          additionalProperties: true
      additionalProperties: false
  securitySchemes:
    secretKey:
      type: http
      scheme: bearer
      description: Tenant secret key (lcr_…). Server-side only.
    sandboxKey:
      type: http
      scheme: bearer
      description: >-
        Sandbox key (lcrsb_…). Metered calls are simulated: no credits move, no
        providers are called. No management access. Simulation is served from
        fixtures for the hosted provider catalog; external-rail providers are
        not registered with the sandbox interceptor and answer 404.
    endUserToken:
      type: http
      scheme: bearer
      description: >-
        60-3600 second end-user JWT minted via /credits/end-users/{id}/token. If
        the JWT has sid, send the original session value in X-Locus-Session-Id;
        sid contains only its SHA-256 fingerprint. Bearer tokens are replayable
        until expiry; use short TTLs, optional session binding, and
        Idempotency-Key on operations.
    agentConnection:
      type: http
      scheme: bearer
      description: >-
        Scoped lcac_ credential. Tenant-managed Agent Connections authorize only
        their bound MCP and wrapped execution surfaces. A bootstrap connection
        for a self-registered agent additionally authorizes the explicit
        /credits/agent/* self-service routes for its own account; neither form
        authorizes general tenant management.

````