> ## Documentation Index > Fetch the complete documentation index at: https://partners.centaur.io/docs/llms.txt > Use this file to discover all available pages before exploring further. # Summarize message and event activity > Returns deterministic message and event counts over an explicit UTC time window, grouped by trader or overall and bucketed by a fixed interval. An Activity Summary is evidence-grade for counts, volumes, and trends; it is not a generated narrative summary. Use this instead of paging raw messages or events to count or trend activity. ## OpenAPI ````yaml /openapi.json get /api/v1/activity-summaries openapi: 3.1.0 info: title: Centaur API version: 1.0.0 description: >- Public, read-only API for Centaur's data over REST with a companion MCP surface. servers: - url: https://partners.centaur.io description: Current service base URL security: [] tags: - name: System description: Health and service metadata endpoints. - name: Discovery description: Read-only trader and asset directory discovery endpoints. - name: Events description: >- Historical trade-event reads with source, trader, asset, and position context. - name: Messages description: >- Read-only access to source messages by message timestamp or Source Message ID. - name: Channel Summaries description: Generated channel narrative summaries selected by Source Window overlap. - name: Aggregate Summaries description: >- Generated aggregate narrative summaries selected by Aggregate Window overlap. - name: Positions description: Read-only position history and open-position live state reads. - name: Stats description: Read-only aggregate trader and asset stats. externalDocs: description: Canonical Centaur API documentation url: https://partners.centaur.io/docs paths: /api/v1/activity-summaries: get: tags: - Rankings summary: Summarize message and event activity description: >- Returns deterministic message and event counts over an explicit UTC time window, grouped by trader or overall and bucketed by a fixed interval. An Activity Summary is evidence-grade for counts, volumes, and trends; it is not a generated narrative summary. Use this instead of paging raw messages or events to count or trend activity. operationId: listActivitySummaries parameters: - schema: allOf: - $ref: '#/components/schemas/ActivitySummaryGroupBy' - description: >- Group counts by `trader` (default) or return one overall group with `none`. required: false description: >- Group counts by `trader` (default) or return one overall group with `none`. name: groupBy in: query - schema: allOf: - $ref: '#/components/schemas/ActivitySummaryInterval' - description: >- Bucket interval: `hour`, `day` (default), or `week`. The window/interval combination is rejected when it would produce more than 168 buckets per group. required: false description: >- Bucket interval: `hour`, `day` (default), or `week`. The window/interval combination is rejected when it would produce more than 168 buckets per group. name: interval in: query - schema: anyOf: - anyOf: - type: string - type: array items: type: string - type: array items: type: number - type: array items: $ref: '#/components/schemas/EventType' description: >- Filter event counts to specific event types: `open`, `close`, `increase`, or `decrease`. required: false description: >- Filter event counts to specific event types: `open`, `close`, `increase`, or `decrease`. name: eventTypes in: query - schema: anyOf: - type: string - type: array items: type: string - type: array items: type: number description: Filter to specific trader IDs. required: false description: Filter to specific trader IDs. name: traderIds in: query - schema: type: string format: date-time description: >- Inclusive ISO-8601 lower time bound. Defaults to 7 days before the applied endTime. required: false description: >- Inclusive ISO-8601 lower time bound. Defaults to 7 days before the applied endTime. name: startTime in: query - schema: type: string format: date-time description: >- Inclusive ISO-8601 upper time bound. Defaults to the current server time. required: false description: >- Inclusive ISO-8601 upper time bound. Defaults to the current server time. name: endTime in: query - schema: type: integer minimum: 1 maximum: 50 description: >- Maximum number of groups to return, ordered by combined activity. Defaults to 10, maximum 50. required: false description: >- Maximum number of groups to return, ordered by combined activity. Defaults to 10, maximum 50. name: limit in: query responses: '200': description: Bounded activity counts per group with per-interval buckets content: application/json: schema: type: object properties: success: type: boolean enum: - true data: $ref: '#/components/schemas/ActivitySummariesResponseData' requestId: type: string example: c8e2c6e4-80dd-4ffc-9d66-4e31bf64c6b8 required: - success - data - requestId '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: success: false error: code: UNAUTHORIZED message: Unauthorized requestId: c8e2c6e4-80dd-4ffc-9d66-4e31bf64c6b8 '403': description: Forbidden content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: success: false error: code: FORBIDDEN message: Forbidden requestId: c8e2c6e4-80dd-4ffc-9d66-4e31bf64c6b8 '422': description: >- Validation error, including window/interval combinations above the bucket limit content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: success: false error: code: BUCKET_LIMIT_EXCEEDED message: >- The requested window would produce too many buckets per group. Widen the interval or narrow the startTime/endTime window. requestId: c8e2c6e4-80dd-4ffc-9d66-4e31bf64c6b8 '503': description: Authentication service temporarily unavailable headers: Retry-After: description: Seconds to wait before retrying authentication schema: type: integer minimum: 1 content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: success: false error: code: AUTHENTICATION_UNAVAILABLE message: Authentication is temporarily unavailable requestId: c8e2c6e4-80dd-4ffc-9d66-4e31bf64c6b8 security: - ApiKeyAuth: [] components: schemas: ActivitySummaryGroupBy: type: string enum: - trader - none ActivitySummaryInterval: type: string enum: - hour - day - week EventType: type: string enum: - open - close - increase - decrease ActivitySummariesResponseData: type: object properties: filtersApplied: type: object properties: groupBy: $ref: '#/components/schemas/ActivitySummaryGroupBy' interval: $ref: '#/components/schemas/ActivitySummaryInterval' eventTypes: type: array items: $ref: '#/components/schemas/EventType' traderIds: type: array items: type: integer appliedTimeRange: $ref: '#/components/schemas/AppliedTimeRange' required: - groupBy - interval - eventTypes - traderIds - appliedTimeRange results: type: array items: $ref: '#/components/schemas/ActivitySummary' meta: type: object properties: totalMessages: type: integer description: >- Total messages across all groups, not only the returned top groups. totalEvents: type: integer description: >- Total events across all groups, not only the returned top groups. required: - totalMessages - totalEvents required: - filtersApplied - results - meta ErrorEnvelope: type: object properties: success: type: boolean enum: - false error: $ref: '#/components/schemas/Error' requestId: type: string example: c8e2c6e4-80dd-4ffc-9d66-4e31bf64c6b8 required: - success - error - requestId AppliedTimeRange: type: object properties: startTime: type: string nullable: true format: date-time endTime: type: string nullable: true format: date-time required: - startTime - endTime ActivitySummary: type: object properties: traderId: type: integer nullable: true description: >- Related trader ID for `groupBy=trader`, null for the overall `groupBy=none` group. messageCount: type: integer description: Total source messages for this group inside the applied time range. eventCount: type: integer description: Total events for this group inside the applied time range. buckets: type: array items: $ref: '#/components/schemas/ActivitySummaryBucket' description: >- Per-interval counts ordered by bucket start. Buckets with no activity are omitted. required: - traderId - messageCount - eventCount - buckets Error: type: object properties: code: type: string description: Stable machine-readable error code. example: UNAUTHORIZED message: type: string description: Human-readable explanation for the failure. example: Unauthorized details: nullable: true description: Optional structured details for validation or input failures. required: - code - message ActivitySummaryBucket: type: object properties: start: type: string format: date-time description: Inclusive UTC bucket start, truncated to the applied interval. end: type: string format: date-time description: Exclusive UTC bucket end. messageCount: type: integer eventCount: type: integer required: - start - end - messageCount - eventCount securitySchemes: ApiKeyAuth: type: apiKey in: header name: x-api-key description: API key issued by Centaur. x-default: ````