> ## Documentation Index > Fetch the complete documentation index at: https://docs.nylon.dev/llms.txt > Use this file to discover all available pages before exploring further. # List network capabilities > Character limits, media specs, post types and options for every network. ## OpenAPI ````yaml /openapi.yaml get /v1/networks openapi: 3.1.0 info: title: Nylon API version: 1.0.0 description: | One API for publishing to twelve social networks. You address a post to connected profile ids; Nylon knows which network each one belongs to, what that network accepts, and how to get the media there. Character limits, media specs, upload protocols and threading rules are normalised before the request reaches a platform, and every failure comes back in one error taxonomy. ## Conventions - Request and response fields are `snake_case`. - Successful responses wrap the payload in `data`. List responses add `meta.pagination`. - Failures return `{ "error": { "code", "message", "details?" } }`. Branch on `code`; `message` is written for humans and may change. - Times are ISO 8601 with a `Z` offset. - Successful responses carry `RateLimit-Limit`, `RateLimit-Remaining` and `RateLimit-Reset`. A `429` carries those plus `Retry-After`. servers: - url: https://api.nylon.dev description: Production security: - bearerAuth: [] tags: - name: Posts description: Create, schedule, inspect, edit and retry posts. - name: Profiles description: Social profiles connected to the authenticated Nylon account. - name: Connections description: Start a connection and see which networks are available. - name: Networks description: What each network accepts, as data. - name: Validation description: Dry-run a post without publishing it. - name: Webhooks description: Endpoints Nylon calls when a post finishes or a profile stops working. paths: /v1/networks: get: tags: - Networks summary: List network capabilities description: | Every network's publishing rules, as data. This is what makes `POST /v1/posts` predictable: the character limits, media counts and sizes, post types and per-network options below come from the same table the validator enforces, so a client can check a post before sending it and get the same answer. Two text limits, and the distinction matters. `per_post` is what one post on the network may carry; `max` is what one request may carry. On the four networks that thread — X, Threads, Bluesky, Mastodon — `max` is much larger, because a long caption becomes a chain of replies rather than an error. operationId: listNetworks parameters: - name: network in: query description: >- Return one network instead of all twelve. Common aliases such as `twitter` resolve to `x`. schema: type: string example: x responses: '200': description: Capabilities per network. content: application/json: schema: $ref: '#/components/schemas/NetworkListResponse' examples: singleNetwork: summary: GET /v1/networks?network=x value: data: - network: x label: X text: max: 5000 per_post: 280 max_hashtags: null threads: true post_types: - post requires_media: false supports_link_only: true allows_mixed_media: false media: image: max: 4 max_bytes: 5242880 video: max: 1 max_bytes: 536870912 duration_ms: max: 140000 gif: max: 1 max_bytes: 15728640 title: null options: - reply_settings '400': description: The `network` parameter is not a network Nylon publishes to. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' '401': $ref: '#/components/responses/Unauthorized' '429': $ref: '#/components/responses/RateLimited' '500': $ref: '#/components/responses/InternalError' components: schemas: NetworkListResponse: type: object required: - data properties: data: type: array items: $ref: '#/components/schemas/NetworkCapabilities' ErrorResponse: type: object required: - error properties: error: $ref: '#/components/schemas/Error' NetworkCapabilities: type: object required: - network - label - text - threads - post_types - media properties: network: $ref: '#/components/schemas/Network' label: type: string example: X text: type: object properties: max: type: integer description: Ceiling for the whole request. example: 5000 per_post: type: integer description: >- Ceiling for a single published post. Equals `max` where there is no threading. example: 280 max_hashtags: type: - integer - 'null' example: null threads: type: boolean description: Whether a long caption is published as a chain of replies. example: true post_types: type: array items: type: string enum: - post - reel - story requires_media: type: boolean description: >- True where a text-only post is impossible — Instagram, Pinterest, TikTok, YouTube. supports_link_only: type: boolean description: Whether a bare link with no media is a usable post. allows_mixed_media: type: boolean description: Whether images and videos may be mixed in one post. media: type: object properties: image: $ref: '#/components/schemas/MediaLimit' video: $ref: '#/components/schemas/MediaLimit' gif: $ref: '#/components/schemas/MediaLimit' title: type: - object - 'null' description: Length bounds for `title`, or null where the network has no title. properties: min: type: integer max: type: integer options: type: array description: >- The keys this network reads from `networks.` on a publish request. items: type: string example: - reply_settings connectable: type: boolean description: | Whether this account could connect one right now. Present when listing all networks; availability is app credentials, not a static list. Error: type: object required: - code - message properties: code: type: string description: The stable identifier to branch on. enum: - invalid_request - unauthorized - payment_required - forbidden - not_found - conflict - rate_limited - unsupported - publish_failed - internal_error example: unauthorized message: type: string description: Written for humans. Do not match on it. example: A valid Nylon API key is required. details: type: array description: Present when the failure has a per-field or per-network breakdown. items: $ref: '#/components/schemas/ErrorDetail' Network: type: string description: A network Nylon publishes to. enum: - facebook - instagram - x - linkedin - pinterest - bluesky - threads - tiktok - youtube - google_business - mastodon - discord example: instagram MediaLimit: type: object required: - max - max_bytes properties: max: type: integer description: >- How many of this kind one post may carry. Zero means the network does not accept it. example: 4 max_bytes: type: - integer - 'null' description: >- Per-file ceiling in bytes. Bytes, not megabytes, to avoid the MB/MiB ambiguity. example: 5242880 duration_ms: type: - object - 'null' description: >- Video duration bounds in milliseconds, where the network states them. properties: min: type: integer example: 3000 max: type: integer example: 140000 ErrorDetail: type: object required: - message properties: field: type: string description: The request field the problem is about. example: profile_ids network: type: string description: The network the problem is about. example: instagram code: type: string description: | Machine-readable identifier for this problem. On a per-network detail this is a publishing code: `invalid_request`, `unsupported`, `media_error`, `reauthentication_required`, `rejected_by_network`, `network_error`, `timeout`, `profile_unavailable` or `internal_error`. example: invalid_request message: type: string example: >- Instagram requires at least 1 media item — text-only posts are not supported. responses: Unauthorized: description: The bearer API key is missing, malformed or revoked. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: missingKey: value: error: code: unauthorized message: A valid Nylon API key is required. RateLimited: description: | Too many requests for this API key. Reads allow 120 requests a minute; publishing endpoints allow 30, because each one costs real upstream calls. The limit is per key, not per IP. headers: Retry-After: $ref: '#/components/headers/RetryAfter' RateLimit-Limit: $ref: '#/components/headers/RateLimitLimit' RateLimit-Remaining: $ref: '#/components/headers/RateLimitRemaining' RateLimit-Reset: $ref: '#/components/headers/RateLimitReset' content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' examples: throttled: value: error: code: rate_limited message: Too many requests. Retry after the window resets. InternalError: description: Nylon encountered an unexpected error. content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' headers: RetryAfter: description: Seconds to wait before retrying. schema: type: integer example: 47 RateLimitLimit: description: Requests allowed in the current window. schema: type: integer example: 120 RateLimitRemaining: description: Requests left in the current window. schema: type: integer example: 119 RateLimitReset: description: Seconds until the window resets. schema: type: integer example: 47 securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: Nylon API key description: An API key beginning with `nylon_live_`. ````