> ## 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 a hosted world session ## OpenAPI ````yaml /api-reference/openapi.json get /v1/projects/{projectId}/sessions/{sessionId} 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}: get: tags: - worlds summary: Read a hosted world session operationId: sessions.get 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: Hosted world session content: application/json: schema: $ref: '#/components/schemas/Session' default: description: Canonical error envelope content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' components: schemas: Session: type: object properties: schemaVersion: type: number enum: - 1 organizationId: type: string pattern: ^org_[0-9a-z]{12,32}$ 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 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 ````