> ## Documentation Index > Fetch the complete documentation index at: https://docs.closient.com/llms.txt > Use this file to discover all available pages before exploring further. # Quantified downstream footprint for one lot > Walks the forward CriticalTrackingEvent chain from the given lot and returns aggregate counts (downstream lots, serials, ship-to GLNs, trading-partner recipients). Same auth + visibility semantics as the FDA traceability export — the requesting user must be an OWNER or MANAGER of the organization that owns the lot's brand. Designed for recall-impact triage (C-734): given a suspect lot, how far has it spread and to whom? Counts are computed over events visible to the requesting organization only. ## OpenAPI ````yaml /openapi/openapi-epcis.json get /epcis/api/2.0/traceability/lots/{lot_id}/blast-radius openapi: 3.1.0 info: title: EPCIS 2.0 API version: 2.0.0 description: > GS1-conformant EPCIS 2.0 event capture and query API. ## Authentication All endpoints require an API key passed via the `X-API-Key` HTTP header, unless otherwise noted. ``` X-API-Key: csb__ ``` Generate API keys in **Settings > API Keys** in your dashboard, or via the Account API. Session-based (cookie) authentication is also accepted for browser-based access. ## Rate Limits | Tier | Requests / minute | Requests / day | |-------------|-------------------|----------------| | Default | 300 | 10,000 | | Custom | Contact us | Contact us | Rate-limit headers are included on every response so callers can self-throttle without hitting our 429s ("informed governor"): - `RateLimit-Policy` — every active window, e.g. `300;w=60, 10000;w=86400` - `RateLimit-Limit` — quota for the **most-restrictive** currently-active window - `RateLimit-Remaining` — requests left in that window - `RateLimit-Reset` — seconds until that window resets (relative; clock-skew safe) Legacy `X-RateLimit-*` aliases are also emitted for back-compat. `X-RateLimit-Reset` keeps the absolute Unix-timestamp shape to avoid breaking existing consumers. When rate-limited, you receive `429 Too Many Requests` with a `retry_after_seconds` field in the error envelope and a `Retry-After` header. ## Pagination List endpoints return paginated results in this envelope: ```json { "data": [...], "pagination": { "page": 1, "page_size": 25, "total_count": 342, "total_pages": 14, "has_next": true, "has_previous": false } } ``` Use `?page=2&page_size=50` query parameters. Maximum page size is 100. ## Error Responses All errors conform to [RFC 9457 Problem Details](https://www.rfc-editor.org/rfc/rfc9457) with `Content-Type: application/problem+json`: ```json { "type": "https://closient.com/docs/errors/not_found", "title": "Not Found", "status": 404, "detail": "The requested resource was not found.", "error_code": "not_found", "retryable": false, "timestamp": "2026-03-31T12:00:00+00:00" } ``` Common error codes: `unauthorized` (401), `forbidden` (403), `not_found` (404), `validation_error` (422), `rate_limited` (429), `internal_error` (500). termsOfService: https://www.closient.com/terms/ servers: - url: https://www.closient.com security: [] externalDocs: description: Closient Documentation url: https://docs.closient.com paths: /epcis/api/2.0/traceability/lots/{lot_id}/blast-radius: get: tags: - EPCIS 2.0 summary: Quantified downstream footprint for one lot description: >- Walks the forward CriticalTrackingEvent chain from the given lot and returns aggregate counts (downstream lots, serials, ship-to GLNs, trading-partner recipients). Same auth + visibility semantics as the FDA traceability export — the requesting user must be an OWNER or MANAGER of the organization that owns the lot's brand. Designed for recall-impact triage (C-734): given a suspect lot, how far has it spread and to whom? Counts are computed over events visible to the requesting organization only. operationId: apps_epcis_api_epcis_traceability_lot_blast_radius parameters: - in: path name: lot_id schema: description: >- Short ID of the ``ProductLot`` to compute the blast radius for — 22-character shortuuid encoding of the lot's UUID primary key. maxLength: 22 minLength: 22 title: Lot Id type: string required: true description: >- Short ID of the ``ProductLot`` to compute the blast radius for — 22-character shortuuid encoding of the lot's UUID primary key. responses: '200': description: OK content: application/json: schema: $ref: '#/components/schemas/BlastRadiusSchema' '401': description: Unauthorized content: application/json: schema: $ref: '#/components/schemas/ErrorOut' '403': description: Forbidden content: application/json: schema: $ref: '#/components/schemas/ErrorOut' '404': description: Not Found content: application/json: schema: $ref: '#/components/schemas/ErrorOut' '429': description: Too Many Requests content: application/json: schema: $ref: '#/components/schemas/ErrorOut' security: - APIKeyHeaderAuth: [] - OAuthTokenAuth: [] - SessionAuth: [] components: schemas: BlastRadiusSchema: description: |- Quantified downstream footprint of a single lot. Counts are computed over events visible to the requesting organization — same access semantics as ``trace_forward``. examples: - affected_organizations: 2 downstream_locations: 3 downstream_lots: 8 downstream_serials: 1240 lot_id: aQ4nF7zG3kmRtXp9LcWyVH properties: lot_id: description: >- Short ID of the source lot the radius was computed for — echoed from the path parameter. 22-character shortuuid encoding. maxLength: 22 minLength: 22 title: Lot Id type: string downstream_lots: description: >- Distinct ``ProductLots`` reached by walking forward CriticalTrackingEvents from the source lot, excluding the source lot itself. Zero when the lot has not yet been observed in any forward event. minimum: 0 title: Downstream Lots type: integer downstream_serials: description: >- Total serialized EPCs (sum of ``epcList`` sizes) allocated across the downstream lots. Approximates the number of physical units potentially affected by a recall on the source lot. minimum: 0 title: Downstream Serials type: integer downstream_locations: description: >- Distinct ship-to GLNs across SHIP CTEs on the source lot or any of its downstream derivatives. Counts unique destination locations (a single location with many shipments counts once). minimum: 0 title: Downstream Locations type: integer affected_organizations: description: >- Distinct trading-partner recipients (resolved via ``OWNING_PARTY`` destinations on SHIP CTEs) across the forward chain. minimum: 0 title: Affected Organizations type: integer required: - lot_id - downstream_lots - downstream_serials - downstream_locations - affected_organizations title: BlastRadiusSchema type: object ErrorOut: description: |- RFC 9457 Problem Details response. All API errors are returned in this format with Content-Type: application/problem+json. examples: - detail: The requested resource was not found. error_code: not_found retryable: false status: 404 timestamp: '2026-03-31T12:00:00+00:00' title: Not Found type: https://closient.com/docs/errors/not_found - detail: Validation error. details: - loc: - body - name msg: Field required type: missing error_code: validation_error retryable: false status: 422 timestamp: '2026-03-31T12:00:00+00:00' title: Validation Error type: https://closient.com/docs/errors/validation_error - detail: Rate limit exceeded. Please try again later. error_code: rate_limited retry_after: 31 retryable: true status: 429 timestamp: '2026-03-31T12:00:00+00:00' title: Rate Limited type: https://closient.com/docs/errors/rate_limited properties: type: description: URI reference identifying the error type. title: Type type: string title: description: Short human-readable summary of the error. title: Title type: string status: description: HTTP status code. title: Status type: integer detail: description: Human-readable explanation of this specific occurrence. title: Detail type: string error_code: description: Machine-readable error code (e.g. not_found, unauthorized). title: Error Code type: string retryable: default: false description: Whether retrying the same request can succeed. title: Retryable type: boolean timestamp: description: ISO 8601 timestamp of when the error occurred. title: Timestamp type: string retry_after: anyOf: - type: integer - type: 'null' description: Seconds to wait before retrying (when applicable). title: Retry After owner_action_required: anyOf: - type: boolean - type: 'null' description: Whether the error requires account owner intervention. title: Owner Action Required details: description: Additional context (validation errors, etc.). title: Details required: - type - title - status - detail - error_code - timestamp title: ErrorOut type: object securitySchemes: APIKeyHeaderAuth: type: apiKey in: header name: X-API-Key OAuthTokenAuth: type: http scheme: bearer SessionAuth: type: apiKey in: cookie name: sessionid ````