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

# Read the atomic runtime position of a ready session



## OpenAPI

````yaml /api-reference/openapi.json get /v1/projects/{projectId}/sessions/{sessionId}/runtime
openapi: 3.1.0
info:
  title: Firedrill Control API
  version: 1.0.0
  description: >-
    The control plane for drills, drill runs, and the worlds they run in. Errors
    always carry the canonical envelope; unsafe operations require an
    Idempotency-Key; long work returns an operation resource.
servers:
  - url: https://api.firedrill.run
security:
  - controlCredential: []
tags:
  - name: authentication
    description: Sessions, CLI exchange, credentials, and verification keys.
    x-group: Authentication
  - name: organizations
    description: Organization members, billing, usage, retention, audit, and exports.
    x-group: Organizations
  - name: projects
    description: Project lifecycle, access, grants, and repository bindings.
    x-group: Projects
  - name: builds
    description: Immutable builds, uploads, source drafts, and world definitions.
    x-group: Builds and source
  - name: tools
    description: Project Tool discovery, approval, source, and revocation.
    x-group: Tool library
  - name: worlds
    description: >-
      Managed environments, world sessions, state, time, reset, faults, forks,
      and snapshots.
    x-group: Environments and sessions
  - name: runs
    description: >-
      Hosted runs, comparisons, attachments, reports, evidence bundles, sharing,
      and exports.
    x-group: Runs and evidence
  - name: browser
    description: Managed browser tests, runs, messages, streams, frames, and artifacts.
    x-group: Browser testing
  - name: callbacks
    description: Callback receiver approval, revocation, and signing material.
    x-group: Callbacks
  - name: github-ci
    description: >-
      GitHub installations, repository automation, CI suites, cases, evidence,
      and checks.
    x-group: GitHub and CI
  - name: authoring
    description: Authoring sessions, proposals, turns, and scenario proposals.
    x-group: Cloud authoring
paths:
  /v1/projects/{projectId}/sessions/{sessionId}/runtime:
    get:
      tags:
        - worlds
      summary: Read the atomic runtime position of a ready session
      operationId: sessions.runtime
      parameters:
        - name: projectId
          in: path
          required: true
          schema:
            type: string
            pattern: ^prj_[0-9a-z]{12,32}$
        - name: sessionId
          in: path
          required: true
          schema:
            type: string
            pattern: ^ses_[0-9a-z]{12,32}$
      responses:
        '200':
          description: Session runtime position
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/SessionRuntimeView'
        default:
          description: Canonical error envelope
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorEnvelope'
components:
  schemas:
    SessionRuntimeView:
      type: object
      properties:
        schemaVersion:
          type: number
          enum:
            - 1
        session:
          type: object
          properties:
            schemaVersion:
              type: number
              enum:
                - 1
            organizationId:
              type: string
              pattern: ^org_[0-9a-z]{12,32}$
            projectId:
              type: string
              pattern: ^prj_[0-9a-z]{12,32}$
            environmentId:
              type: string
              pattern: ^env_[0-9a-z]{12,32}$
            sessionId:
              type: string
              pattern: ^ses_[0-9a-z]{12,32}$
            buildHash:
              type: string
              pattern: ^sha256:[0-9a-f]{64}$
            drillId:
              description: >-
                Run-ready setup from this drill. Mutually exclusive with
                scenarioId; omit both selectors for the build baseline.
              type: string
              minLength: 1
              maxLength: 96
              pattern: ^[a-z][a-z0-9]*(?:[-_][a-z0-9]+)*$
            scenarioId:
              description: >-
                Standalone setup from this compiled scenario, without a drill or
                target. Mutually exclusive with drillId.
              type: string
              minLength: 1
              maxLength: 96
              pattern: ^[a-z][a-z0-9]*(?:[-_][a-z0-9]+)*$
            seed:
              type: string
              minLength: 1
              maxLength: 20
            callbackReceiverBindingIds:
              default: []
              maxItems: 64
              type: array
              items:
                type: string
                pattern: ^cbr_[0-9a-z]{12,32}$
            state:
              type: string
              enum:
                - creating
                - warming
                - ready
                - resetting
                - degraded
                - expired
                - destroying
                - destroyed
            warmPool:
              description: >-
                Explicitly reserved warm-world lineage. Only claimed worlds can
                become ready for agent access.
              type: object
              properties:
                state:
                  type: string
                  enum:
                    - preparing
                    - ready
                    - claimed
                    - retired
                setupHash:
                  type: string
                  pattern: ^sha256:[0-9a-f]{64}$
              required:
                - state
                - setupHash
              additionalProperties: false
            leaseGeneration:
              type: integer
              minimum: 0
              exclusiveMinimum: true
              maximum: 9007199254740991
            parentSessionId:
              type: string
              pattern: ^ses_[0-9a-z]{12,32}$
            parentHostedSnapshotId:
              type: string
              pattern: ^hsnap_[0-9a-z]{12,32}$
            createdAtMs:
              type: integer
              minimum: -9007199254740991
              maximum: 9007199254740991
            updatedAtMs:
              type: integer
              minimum: -9007199254740991
              maximum: 9007199254740991
            expiresAtMs:
              type: integer
              minimum: -9007199254740991
              maximum: 9007199254740991
            destroyedAtMs:
              type: integer
              minimum: -9007199254740991
              maximum: 9007199254740991
            version:
              type: integer
              minimum: -9007199254740991
              maximum: 9007199254740991
          required:
            - schemaVersion
            - organizationId
            - projectId
            - environmentId
            - sessionId
            - buildHash
            - seed
            - callbackReceiverBindingIds
            - state
            - leaseGeneration
            - createdAtMs
            - updatedAtMs
            - expiresAtMs
            - version
          additionalProperties: false
          not:
            required:
              - drillId
              - scenarioId
        hostedRunId:
          description: >-
            The run owning this exact world lease. Use its interaction-scoped
            connection; reset before standalone use after completion.
          type: string
          pattern: ^hrun_[0-9a-z]{12,32}$
        actors:
          type: array
          items:
            type: object
            properties:
              actorId:
                type: string
                minLength: 1
                maxLength: 96
                pattern: ^[a-z][a-z0-9]*(?:[-_][a-z0-9]+)*$
              actorBindingId:
                type: string
                pattern: ^actor_[A-Za-z0-9][A-Za-z0-9_-]{5,95}$
              capabilities:
                type: array
                items:
                  type: object
                  properties:
                    packageId:
                      type: string
                      minLength: 1
                      maxLength: 96
                      pattern: ^[a-z][a-z0-9]*(?:[-_][a-z0-9]+)*$
                    operationId:
                      type: string
                      minLength: 1
                      maxLength: 160
                      pattern: >-
                        ^[a-z][a-z0-9]*(?:[-_][a-z0-9]+)*(?:\.[a-z][a-z0-9]*(?:[-_][a-z0-9]+)*)*$
                  required:
                    - packageId
                    - operationId
                  additionalProperties: false
            required:
              - actorId
              - actorBindingId
              - capabilities
            additionalProperties: false
        position:
          type: object
          properties:
            virtualTimeUs:
              type: integer
              minimum: -9007199254740991
              maximum: 9007199254740991
            evidenceSequence:
              type: integer
              minimum: -9007199254740991
              maximum: 9007199254740991
            stateHash:
              type: string
              pattern: ^sha256:[0-9a-f]{64}$
            evidenceHash:
              type: string
              pattern: ^sha256:[0-9a-f]{64}$
            consistency:
              type: string
              enum:
                - atomic
          required:
            - virtualTimeUs
            - evidenceSequence
            - stateHash
            - evidenceHash
            - consistency
          additionalProperties: false
      required:
        - schemaVersion
        - session
        - position
      additionalProperties: false
    ErrorEnvelope:
      type: object
      properties:
        code:
          type: string
          pattern: ^(control|world)\.[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$
        message:
          type: string
          minLength: 1
        correlationId:
          type: string
          minLength: 1
        retryable:
          type: boolean
        retryAfterMs:
          type: integer
          exclusiveMinimum: 0
          maximum: 9007199254740991
        operationId:
          type: string
        source:
          type: string
          enum:
            - platform
            - simulated_provider
        issues:
          type: array
          items:
            type: object
            properties:
              path:
                type: string
              code:
                type: string
              message:
                type: string
            required:
              - path
              - code
              - message
            additionalProperties: false
        details:
          type: object
          propertyNames:
            type: string
          additionalProperties: {}
        evidence:
          type: object
          properties:
            sessionId:
              type: string
            runId:
              type: string
            journalSeq:
              type: integer
              minimum: 0
              maximum: 9007199254740991
            buildHash:
              type: string
          additionalProperties: false
      required:
        - code
        - message
        - correlationId
        - retryable
        - source
      additionalProperties: true
  securitySchemes:
    controlCredential:
      type: http
      scheme: bearer
      description: Opaque control credential

````