> ## Documentation Index > Fetch the complete documentation index at: https://docs.orq.ai/llms.txt > Use this file to discover all available pages before exploring further. # Annotate a span > Attach one or more annotations to a specific span. A standard annotation references a human review by key and supplies a value. A correction references an existing evaluator output by parent_annotation_id and supplies the corrected value, validated against that evaluator's output schema. **Related guide**: Annotations guide. See the [Annotations guide](/ai-studio/observability/annotations) for a walkthrough with examples. The `trace_id` and `span_id` path parameters identify the span to annotate. Get them from the [`telemetry` object](/ai-gateway/features/responses-api#telemetry) on a router response, the `x-orq-trace-id` and `x-orq-trace-span-id` response headers, or the [Traces](/ai-studio/observability/traces) view. ## OpenAPI ````yaml post /v2/traces/{trace_id}/spans/{span_id}/annotation openapi: 3.1.0 info: title: orq.ai API version: '2.0' description: orq.ai API documentation servers: - url: https://my.orq.ai security: - ApiKey: [] tags: - name: Chunking description: Split text into smaller chunks for retrieval and generation workflows. - name: File Systems description: >- Create and manage persistent file systems that agents and MCP clients read from and write to. - name: Knowledge Bases description: Create and manage knowledge bases used by agents and retrieval workflows. - name: Memory Stores description: Create and manage memory stores, memories, and memory documents. - name: Evals description: Run an evaluator against a conversation and its result - name: Logs description: >- OpenTelemetry log query API. Search, filter, aggregate, and facet log records ingested via OTLP. - name: Reporting description: >- GenAI reporting API over canonical analytics rollups. Accepts a metric name, time range, grain, group-by, and filters; returns a typed time series and optional totals. - name: Traces description: >- Query and inspect ingested trace data: search trace summaries, aggregate metrics, and read individual traces and their spans. - description: List models available through the AI Router. name: Models - name: Policies - name: Alerts description: >- Alerts evaluate a Reporting API metric on a fixed interval and fire notifications through notifiers when the value breaches a threshold. Each breach opens a trigger that tracks the incident until the value recovers. - name: Annotation Queues description: Annotation queues collect spans for human review. - name: API keys description: >- API keys authenticate programmatic access to the workspace. They expose opaque tokens, per-domain access grants, and budget and rate-limit constraints. - name: Audit Logs description: Audit logs record workspace entity changes and access-relevant events. - name: Budgets description: >- Budgets govern spend, token usage, and request rate across six scopes: workspace, project, identity, API key, provider, and model. Every applicable budget is enforced, and the most restrictive limit applies per dimension. - name: Files description: File upload and retrieval operations. - name: Guardrail Rules description: >- Guardrail Rules conditionally enforce evaluators and plugins for AI Gateway traffic. Rules may be scoped to a project or the whole workspace. - name: Hub description: Hub items are reusable templates available to a workspace. - name: Identities description: >- Identities represent end users from your system for usage and engagement tracking. - name: Management keys description: >- Management keys are workspace-scoped credentials that authenticate programmatic access to workspace administration surfaces (API keys, budgets). Unlike project-scoped API keys, a management key always operates at the workspace level. - name: MCP Gateway description: >- Register upstream MCP servers, discover and sync their tools, and assemble gateways that expose a curated tool surface to MCP clients. - name: Model Catalog description: >- Browse the orq.ai model catalog: every model orq offers, across every provider, with pricing, capabilities and benchmark data. List endpoints only return models that are not deprecated. This API is public, requires no authentication, and is rate limited to 120 requests per minute per IP. Responses carry a 5-minute cache-control max-age. - name: Notifiers description: Notifier destinations used to send delivery and workflow notifications. - name: Projects description: Projects organize resources within a workspace - name: Routing Rules description: >- Routing Rules conditionally select models and enforce request plugins for AI Gateway traffic. Rules are evaluated by ascending priority and may be scoped to a project or the whole workspace. - name: Threads description: Threads group related trace invocations and their aggregate usage - name: Skills description: >- Skills are modular instructions you can use to codify processes and conventions - name: Smart Routers description: >- Create and manage workspace Smart Routers. A Smart Router selects a model from an eligible pool for each request according to a quality, balanced, or cost profile. - name: Webhooks description: >- Create and manage webhooks that deliver workspace events to external HTTPS endpoints. - name: Workspaces description: >- A workspace is the tenant. Create is called from a user session during onboarding; Get, List, and Update are the public management surface. - name: Workspace Security description: >- Workspace-level domain verification and IP allowlist controls. These operations are restricted to workspace administrators. - name: Workspace Settings description: >- Workspace-level settings managed with a workspace credential. A workspace is the tenant, so these settings are a singleton — there is nothing to create or delete, only read and update. - name: Responses - description: Run agents on a cron cadence. Minimum firing interval is 1 hour. name: Agent Schedules - name: Embeddings - name: Telemetry description: >- Unified query envelope for traces, metrics, and logs. One request shape, one filter dialect, and one response shape per source, validated by a per-source registry. - description: Beta. Run typed classification questions against a classify model. name: Classify - description: Search Gateway with managed credits or BYOK. name: Web Search externalDocs: url: https://docs.orq.ai description: orq.ai Documentation paths: /v2/traces/{trace_id}/spans/{span_id}/annotation: post: tags: - Annotations summary: Annotate a span description: >- Attach one or more annotations to a specific span. A standard annotation references a human review by key and supplies a value. A correction references an existing evaluator output by parent_annotation_id and supplies the corrected value, validated against that evaluator's output schema. operationId: CreateAnnotation parameters: - schema: type: string description: Unique identifier of the trace required: true description: Unique identifier of the trace name: trace_id in: path - schema: type: string description: Unique identifier of the span required: true description: Unique identifier of the span name: span_id in: path requestBody: content: application/json: schema: type: object properties: annotations: type: array items: anyOf: - type: object properties: key: type: string description: Unique key of the review. value: anyOf: - type: string minLength: 0 maxLength: 3000 - type: number - type: boolean - type: array items: type: string minItems: 1 description: >- The feedback value. For single-select, provide a string or single-element array. For multi-select, provide an array of strings. For range evaluations, provide a number. For boolean, provide a boolean. For text/correction, provide a string. required: - key - value additionalProperties: false - type: object properties: parent_annotation_id: type: string description: >- The eval id of the evaluator annotation being corrected. value: anyOf: - type: string minLength: 0 maxLength: 3000 - type: number - type: boolean - type: array items: type: string minItems: 1 description: >- The feedback value. For single-select, provide a string or single-element array. For multi-select, provide an array of strings. For range evaluations, provide a number. For boolean, provide a boolean. For text/correction, provide a string. explanation: type: string maxLength: 3000 description: Optional explanation for the correction. required: - parent_annotation_id - value additionalProperties: false minItems: 1 maxItems: 10 metadata: type: object properties: identity_id: type: string required: - annotations responses: '200': description: Span annotated components: securitySchemes: ApiKey: type: http scheme: bearer bearerFormat: JWT ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.