> ## Documentation Index > Fetch the complete documentation index at: https://docs.airscale.io/llms.txt > Use this file to discover all available pages before exploring further. # Add sources to a post engagement monitor > Follow more LinkedIn company pages or profiles, up to 100 per monitor. Rate limit: 120 requests per fixed minute per API key, shared by all post engagement monitor endpoints. > [!NOTE] > > Post engagement monitoring requires a **V2 workspace API key**. Legacy V1 API keys are not supported by these endpoints. Monitors and their credits belong to the V2 workspace associated with the key. Add sources with `{"sources": ["https://www.linkedin.com/in/example-person-2"]}`. Each URL must be a LinkedIn company (`/company/...`) or profile (`/in/...`) URL; single post URLs are rejected with `422 invalid_sources`. The `201` response returns `sources` (all active sources), `added_source_count` (URLs already followed are ignored), and `source_count`. A monitor follows at most **100 sources**; exceeding it returns `422 source_limit_reached`. > [!NOTE] > > Adding sources restarts coverage for the monitor. Delivered engagers and the results table are kept, and people already delivered are never charged again. The JSON request body must be at most **256 KiB (262,144 bytes)**. Adding sources spends no credits. ## Next step Use [Get a post engagement monitor](https://docs.airscale.io/api-reference/post-engagement-monitors/get.md) to follow the first check of each new source. ## OpenAPI ````yaml openapi.json POST /v1/post-engagement-monitors/{monitor_id}/sources openapi: 3.1.0 info: title: Airscale Public API version: '2026-09-11' description: >- Search, enrich, resolve public business data, and monitor job changes with Airscale. x-airscale-source-repository: ViceScale/airscale-code x-airscale-source-sha: 1de19e1b70a052a4b8d9c2075021a7e5e7a94d51 servers: - url: https://api.airscale.io description: Production security: - bearerAuth: [] tags: - name: Search and discovery description: Search people, companies, and the web. - name: Contact data description: Find professional and personal contact data. - name: Profiles and reverse lookup description: Extract profiles or resolve a person from known contact data. - name: Post engagement description: Retrieve and enrich people who liked or commented on LinkedIn posts. - name: LinkedIn content description: >- Search LinkedIn posts, read profile and company feeds, and retrieve profile comments and comment reactions. - name: Job change monitoring description: Track LinkedIn profiles and receive job-change events. - name: New hire monitoring description: Watch companies or the market for people who start a matching role. - name: Post engagement monitoring description: >- Follow LinkedIn company pages and profiles and receive the people who engage with their posts. - name: Account description: Inspect workspace account state. - name: Miscellaneous description: >- Find website technologies and check WhatsApp availability, Meta ads, and email deliverability. paths: /v1/post-engagement-monitors/{monitor_id}/sources: post: tags: - Post engagement monitoring summary: Add sources to a monitor description: >- Adds LinkedIn company or profile URLs to a monitor, up to 100 active sources in total. URLs the monitor already follows are ignored. Adding sources restarts coverage for the monitor; delivered engagers and the results table are kept. Requires a V2 workspace API key. Legacy V1 API keys are not supported. Monitors and their credits belong to the V2 workspace. operationId: addPostEngagementMonitorSources parameters: - name: monitor_id in: path required: true schema: type: string format: uuid example: 71111111-1111-4111-8111-111111111111 requestBody: required: true description: >- Provide 1–100 LinkedIn company or profile URLs in a JSON body of at most 256 KiB (262,144 bytes). content: application/json: schema: type: object additionalProperties: false required: - sources properties: sources: type: array minItems: 1 maxItems: 100 items: type: string minLength: 1 maxLength: 1000 description: >- 1–100 LinkedIn company (/company/...) or personal profile (/in/...) URLs. URLs are canonicalized and de-duplicated. Single post URLs are rejected. examples: sources: summary: Follow one more profile value: sources: - https://www.linkedin.com/in/example-person-2 responses: '201': description: The monitor's active sources after the addition. content: application/json: schema: type: object additionalProperties: false required: - sources - added_source_count - source_count properties: sources: type: array items: $ref: '#/components/schemas/PostEngagementSource' description: All active sources after the addition. added_source_count: type: integer minimum: 0 maximum: 100 source_count: type: integer minimum: 0 maximum: 100 examples: success: summary: Successful response value: sources: - id: 72222222-2222-4222-8222-222222222222 linkedin_url: https://www.linkedin.com/company/example-company kind: company status: monitoring last_checked_at: '2026-11-02T09:00:00.000Z' last_error: null - id: 72222223-2222-4222-8222-222222222223 linkedin_url: https://www.linkedin.com/in/example-person kind: profile status: monitoring last_checked_at: '2026-11-02T09:00:00.000Z' last_error: null - id: 72222224-2222-4222-8222-222222222224 linkedin_url: https://www.linkedin.com/in/example-person-2 kind: profile status: pending last_checked_at: null last_error: null added_source_count: 1 source_count: 3 '400': description: >- The request body is missing or is not valid JSON. The public API returns {"error":"Invalid JSON"}. content: application/json: schema: $ref: '#/components/schemas/Error' examples: error: summary: Error response value: error: Invalid JSON '401': $ref: '#/components/responses/MonitorUnauthorized' '404': description: monitor_not_found in this workspace. content: application/json: schema: $ref: '#/components/schemas/MonitorApiError' examples: error: summary: Error response value: error: code: monitor_not_found message: Monitor not found '413': description: The JSON request body exceeds the 256 KiB (262,144 bytes) limit. content: application/json: schema: $ref: '#/components/schemas/Error' '422': description: >- invalid_sources (for example an unknown field, a URL that is not a LinkedIn company or profile, or a single post URL) or source_limit_reached when the monitor would follow more than 100 sources. content: application/json: schema: $ref: '#/components/schemas/MonitorApiError' '429': description: >- The API key has exceeded 120 requests in the current minute across post engagement monitor endpoints. Wait for the Retry-After seconds before retrying. content: application/json: schema: $ref: '#/components/schemas/Error' examples: error: summary: Error response value: error: Too Many Requests message: 'Rate limit exceeded: 120 requests per minute' headers: Retry-After: description: Seconds to wait before retrying. schema: type: string example: '60' '503': description: >- service_unavailable: post engagement monitoring is temporarily unavailable. content: application/json: schema: $ref: '#/components/schemas/MonitorApiError' components: schemas: PostEngagementSource: type: object additionalProperties: false required: - id - linkedin_url - kind - status - last_checked_at - last_error properties: id: type: string format: uuid linkedin_url: type: string kind: type: string enum: - company - profile - post description: >- The API accepts company and profile sources only; post appears on single-post sources added in the Airscale app. status: type: string enum: - pending - monitoring - removed description: >- pending until the source's first check, then monitoring. removed appears only in a remove response. last_checked_at: type: - string - 'null' format: date-time last_error: type: - string - 'null' Error: type: object additionalProperties: true properties: error: type: string message: type: string MonitorApiError: type: object additionalProperties: false required: - error properties: error: type: object additionalProperties: false required: - code - message properties: code: type: string message: type: string responses: MonitorUnauthorized: description: >- A missing Bearer token returns {"error":"Unauthorized","message":"Missing or invalid bearer token"}. An unknown API key returns invalid_api_key. content: application/json: schema: oneOf: - $ref: '#/components/schemas/MonitorApiError' - $ref: '#/components/schemas/Error' examples: invalidKey: summary: Unknown API key value: error: code: invalid_api_key message: The API key is not valid securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: API key description: >- Use an Airscale workspace API key. Never expose the key in client-side code. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.