> ## Documentation Index > Fetch the complete documentation index at: https://docs.superx.so/llms.txt > Use this file to discover all available pages before exploring further. # Draft one reply to a post > Writes ONE reply draft in the account's own voice, using the same engine, prompts and voice settings as the Generate Reply button in the SuperX app. **The draft is text. A person posts it.** No endpoint in this API posts a reply, and this one does not either: it returns wording for someone to read, edit and send from X or from the SuperX app. Sending replies that read as inauthentic can get an X account suspended under X's inauthentic-behavior rules and a SuperX account terminated. AI output must be reviewed and meaningfully edited by a person before it is posted. Name the post exactly one of two ways: - `post_id` reads the post LIVE, so the draft sees the real text, the real author and the quoted post if there is one. That read costs one live lookup on top of the credit, from the same allowance the `/v1/x/*` endpoints use. - `post` supplies the text (and optionally the author) yourself, and nothing is read live. Add `conversation` (oldest first) when the post sits in a thread, and `quoted_post` when it quotes something you already have. `thoughts` is what the person wants the reply to convey: ask them for it rather than inventing an opinion on their behalf. `tone` picks the register. Costs AI credits, measured from the models' real cost and typically 2 (the reply write plus the shared post-editor pass that runs after it). Needs a key with the `write` scope. Accounts shared with you work here: the draft changes nothing on the account, and the credits come from the key owner's pool. ## OpenAPI ````yaml /api-reference/openapi.yaml post /v1/engage/reply-draft openapi: 3.1.0 info: title: SuperX API version: 1.0.0 description: > The SuperX public API: your Twitter/X content, analytics, audience and scheduling data over REST. All endpoints require an API key (`Authorization: Bearer sxk_...`) except `GET /v1/docs`. Keys are created in the SuperX app under Account > API / MCP / CLI and are server-side secrets. Timestamps are UTC ISO-8601 in both directions; inputs must carry an explicit `Z` or numeric offset. Every authenticated response carries `X-RateLimit-Limit`, `X-RateLimit-Remaining` and `X-RateLimit-Reset` headers. contact: name: SuperX url: https://superx.so servers: - url: https://api.superx.so security: - apiKey: [] tags: - name: Identity - name: Content - name: Analytics - name: Inspiration - name: Audience - name: Contact Lists - name: Signals - name: Datasets description: | The audience collections Ask SuperX builds in the app: the repliers, quoters or reposters of a post, the members of an X list, your own posts or replies, or a research brief. Collect a new one with `POST /v1/datasets` (a big collection answers 202 and finishes in the background), read it, export it, or copy the people in it into a contact list you created. Datasets are kept for 30 days, and the ones Ask SuperX builds in the app show up here too. - name: Engage description: | The account's saved Engage feeds and the candidate posts in them, for an agent to score and a person to act on. Read-only by design. These endpoints return feed candidates for a person to review; replies are written and sent by a person in the SuperX app, which is why there is no reply endpoint here. Sending spammy, automated, or AI-generated replies that read as inauthentic may get your X account suspended under X's inauthentic-behavior rules and your SuperX account terminated. AI suggestions must be reviewed and meaningfully edited before they are sent, and you are solely responsible for what you post. Reply activity is logged and may be audited. - name: X Lookups description: | Read any public post, its top replies, any public profile, or an account's latest posts LIVE from X, rather than from SuperX's stored data. These are owner-scoped, so none of them take an `account_id`: nothing about a public lookup is per-X-account. They cost the tighter live-enrichment allowance and share a daily allowance of 300 live lookups with Ask SuperX inside the app, so use them for what you actually need rather than to sweep. Repeat lookups within 15 minutes may be served from a short-lived server-side cache. - name: Tools description: | The composer helpers from the SuperX app, over the API: rewrite a post, edit one selected piece of it, apply one preset rewrite, check a claim, or compare two versions. Every one of them returns TEXT and writes nothing. Nothing here is posted, scheduled or sent; save what you keep with `POST /v1/posts/draft` or `POST /v1/scheduled-posts`. They cost AI credits, measured from the models' real cost, and spend no live-data allowance. - name: Media - name: Workers description: | The posts the account's Workers have written, and the three things a person does with one: save it as a draft, schedule it, or dismiss it. A Worker is a scheduled AI writer set up in the SuperX app. Creating, editing and running one stays in the app, so there is no create or run endpoint here. What a run produces lands in the app's "To review" queue and is read with `GET /v1/workers/suggestions`. NOTHING HERE POSTS TO X. Drafting or scheduling a suggestion writes a post the user can see in the app and on `GET /v1/scheduled-posts`, exactly like the app's own buttons. AI output must be reviewed and meaningfully edited by a person before it goes out, so show the text to the user and confirm the time before you schedule anything. - name: Scheduling - name: Tags - name: Context - name: Queue - name: DMs description: | Queue direct messages into the account's own DM pipeline, and read or cancel what is waiting. NOTHING HERE SENDS A MESSAGE. `POST /v1/dm/campaigns` enqueues; the SuperX app's scheduler is what sends, within the account's daily and monthly DM limits, so the create response is counts, not deliveries. Unsent messages can be cancelled until the scheduler picks them up. You are responsible for the messages you queue. Unsolicited or automated bulk DMs may get an X account suspended under X's rules and a SuperX account terminated, so confirm the recipient list and the exact wording with the person on whose behalf you are queueing. - name: Articles - name: Meta paths: /v1/engage/reply-draft: post: tags: - Engage summary: Draft one reply to a post description: | Writes ONE reply draft in the account's own voice, using the same engine, prompts and voice settings as the Generate Reply button in the SuperX app. **The draft is text. A person posts it.** No endpoint in this API posts a reply, and this one does not either: it returns wording for someone to read, edit and send from X or from the SuperX app. Sending replies that read as inauthentic can get an X account suspended under X's inauthentic-behavior rules and a SuperX account terminated. AI output must be reviewed and meaningfully edited by a person before it is posted. Name the post exactly one of two ways: - `post_id` reads the post LIVE, so the draft sees the real text, the real author and the quoted post if there is one. That read costs one live lookup on top of the credit, from the same allowance the `/v1/x/*` endpoints use. - `post` supplies the text (and optionally the author) yourself, and nothing is read live. Add `conversation` (oldest first) when the post sits in a thread, and `quoted_post` when it quotes something you already have. `thoughts` is what the person wants the reply to convey: ask them for it rather than inventing an opinion on their behalf. `tone` picks the register. Costs AI credits, measured from the models' real cost and typically 2 (the reply write plus the shared post-editor pass that runs after it). Needs a key with the `write` scope. Accounts shared with you work here: the draft changes nothing on the account, and the credits come from the key owner's pool. operationId: draftEngageReply requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ReplyDraftRequest' examples: by_post_id: summary: Read the post live value: post_id: '1899000000000000000' thoughts: agree, and we saw the same thing after switching onboarding tone: concise by_text: summary: Supply the post yourself value: post: text: Most founders think they have a traffic problem. author_name: Pieter Levels author_handle: levelsio tone: engaging responses: '200': description: The reply draft. headers: X-Credits-Charged: $ref: '#/components/headers/X-Credits-Charged' X-Credits-Remaining: $ref: '#/components/headers/X-Credits-Remaining' X-Credits-Reset: $ref: '#/components/headers/X-Credits-Reset' content: application/json: schema: type: object properties: data: type: object properties: reply: type: string description: The draft reply. Nothing was posted or sent. post_id: type: string nullable: true description: The post replied to, when you named one by id. author_handle: type: string nullable: true description: >- The author replied to, without the @, when it is known. meta: $ref: '#/components/schemas/ToolMeta' note: type: string example: data: reply: had the exact same thing, it was positioning the whole time post_id: '1899000000000000000' author_handle: levelsio meta: credits_charged: 2 account_id: '1178367350552305665' note: >- The draft is text. Nothing is posted or sent; a person reviews and posts it. '400': $ref: '#/components/responses/InvalidParameter' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/WriteForbidden' '404': description: No public post with that id, or it is protected or deleted. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: error: code: post_not_found message: No public post with that id. '422': description: >- The post was read but carries no text to reply to. Supply the text yourself with `post`. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: error: code: post_has_no_text message: >- That post carries no text to reply to. Supply the text yourself with `post` instead. '429': $ref: '#/components/responses/AiActionLimited' '500': $ref: '#/components/responses/InternalError' '502': $ref: '#/components/responses/UpstreamError' '503': $ref: '#/components/responses/AccountsUnavailable' components: schemas: ReplyDraftRequest: type: object description: Exactly one of post_id and post is required. properties: post_id: type: string pattern: ^[0-9]{1,25}$ description: >- An X post id. The API reads the post live, which costs one live lookup on top of the credit. post: $ref: '#/components/schemas/ReplyPostShape' conversation: type: array maxItems: 10 description: The thread so far, OLDEST FIRST, so the reply fits the conversation. items: $ref: '#/components/schemas/ReplyPostShape' quoted_post: allOf: - $ref: '#/components/schemas/ReplyPostShape' description: >- The post that the post being replied to quotes. Filled in automatically when you pass post_id. thoughts: type: string maxLength: 2000 description: >- What the person wants the reply to convey. Ask them; do not invent an opinion for them. tone: type: string enum: - engaging - humorous - creative - sarcastic - inspirational - concise account_id: type: string ToolMeta: type: object description: What the call cost and which account it ran as. properties: credits_charged: type: integer description: AI credits kept for this call, settled from the models' real cost. account_id: type: string description: The X account the call ran as. ErrorEnvelope: type: object required: - error properties: error: type: object required: - code - message properties: code: type: string description: Stable machine-readable error code. message: type: string retry_after: type: integer description: Seconds to wait before retrying (rate-limit errors only). ReplyPostShape: type: object required: - text description: A post, supplied by you rather than read from X. properties: text: type: string minLength: 1 maxLength: 4000 author_name: type: string maxLength: 200 description: The author's display name. author_handle: type: string maxLength: 200 description: The author's handle. A leading @ is accepted and stripped. LegacyErrorEnvelope: type: object required: - error description: | Legacy shape used ONLY by the shared subscription middleware: a plain string `error` field. Seen on `403` when the subscription has lapsed (string starts with "subscription_required:") and on `500` when subscription verification fails (string starts with "internal_error:"). properties: error: type: string example: >- subscription_required: The SuperX API requires an active subscription CreditExhaustedError: type: object required: - error description: | The `429 ai_credits_exhausted` body: the standard envelope plus the credit counters. Sent with a `Retry-After` header and the `X-Credits-Remaining` / `X-Credits-Reset` headers. `code` is stable; the counters are additive fields, safe to ignore. properties: error: type: object required: - code - message properties: code: type: string enum: - ai_credits_exhausted message: type: string credits_required: type: integer description: Credits the call needed. credits_remaining: type: integer nullable: true description: Credits available when it was refused. reset_at: type: integer nullable: true description: Unix timestamp (seconds) when the pool refills. ActionLimitedError: type: object required: - error description: | The `429 ai_action_limited` body: a per-day cap on how many times an expensive action can run, counted separately from the credit pool and from the request rate limits. Sent with a `Retry-After` header. Caps reset at midnight UTC. Read `scope` before telling a user anything: `account` means the plan's own daily cap for that action, `platform` means the platform-wide fair-use ceiling on live-data actions, which is shared with every SuperX account. A `platform` refusal is not about this account's quota, so wait and retry rather than reporting the account as out. properties: error: type: object required: - code - message properties: code: type: string enum: - ai_action_limited message: type: string scope: type: string enum: - account - platform description: | Whose ceiling refused the call: this account's own per-day cap for the action, or the platform-wide fair-use ceiling on live-data actions. retry_after: type: integer description: Seconds to wait before the cap resets. reset_at: type: integer description: Unix seconds when the cap resets (the next UTC midnight). headers: X-Credits-Charged: description: >- AI credits kept for this call. Sent on every endpoint that settles its charge before answering, which is all of them except the ones that answer 202 and finish in the background. schema: type: integer X-Credits-Remaining: description: AI credits left in the account's pool, bonus credits included. schema: type: integer X-Credits-Reset: description: Unix timestamp (seconds) when the AI credit pool refills. schema: type: integer responses: InvalidParameter: description: A parameter is missing, malformed, or out of range. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: error: code: invalid_parameter message: since must be a UTC ISO-8601 timestamp Unauthorized: description: >- Missing/malformed Authorization header (`unauthorized`) or an unknown/revoked key (`invalid_api_key`). content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: error: code: invalid_api_key message: Unknown or revoked API key WriteForbidden: description: >- Read-only key (`insufficient_scope`), an account shared with you (`writes_main_account_only`; shared accounts are read-only through the API, your own linked accounts are not), or a lapsed subscription (legacy string envelope). content: application/json: schema: oneOf: - $ref: '#/components/schemas/ErrorEnvelope' - $ref: '#/components/schemas/LegacyErrorEnvelope' example: error: code: insufficient_scope message: >- This API key is read-only. Create a key with the write scope to use this endpoint. AiActionLimited: description: | Rate limited (`rate_limited`, honor `Retry-After`), the AI credit pool is used up (`ai_credits_exhausted`, with the credit counters), or a daily cap on the action was hit (`ai_action_limited`). On `ai_action_limited`, `error.scope` says which ceiling. `account` is one of your own: the plan's daily cap for a metered action, the once-an-hour limit on style guide regeneration (where `reset_at` is an hour after the last run rather than midnight), the 3 live style-guide attempts a day, or the 20 page reads a day shared with the SuperX app. `platform` is the platform-wide fair-use ceiling on live-data actions, shared with every SuperX account: a `platform` refusal is not about this account's quota, so wait for `reset_at` and retry. The free endpoints send `X-Credits-Remaining` and `X-Credits-Reset` on this 429 as they do on a 200, since nothing was charged either way. headers: Retry-After: description: Seconds to wait before retrying. Sent on every flavour of this 429. schema: type: integer X-Credits-Remaining: description: Credits left in the pool. Sent only on `ai_credits_exhausted`. schema: type: integer X-Credits-Reset: description: >- Unix seconds when the pool refills. Sent only on `ai_credits_exhausted`. schema: type: integer content: application/json: schema: anyOf: - $ref: '#/components/schemas/CreditExhaustedError' - $ref: '#/components/schemas/ActionLimitedError' - $ref: '#/components/schemas/ErrorEnvelope' examples: ai_action_limited_account: value: error: code: ai_action_limited message: >- Daily limit reached for this action on your plan (10 lead searches per day). It resets at midnight UTC. scope: account retry_after: 20400 reset_at: 1789430400 ai_action_limited_platform: value: error: code: ai_action_limited message: >- The platform-wide fair-use ceiling for live-data actions has been reached for today. It resets at midnight UTC. scope: platform retry_after: 20400 reset_at: 1789430400 ai_credits_exhausted: value: error: code: ai_credits_exhausted message: Not enough AI credits. Resets in 5 hours. credits_required: 2 credits_remaining: 0 reset_at: 1790812800 InternalError: description: >- Unexpected server error. May also use the legacy string envelope when subscription verification fails. content: application/json: schema: oneOf: - $ref: '#/components/schemas/ErrorEnvelope' - $ref: '#/components/schemas/LegacyErrorEnvelope' example: error: code: internal_error message: Failed to fetch posts UpstreamError: description: A dependent SuperX service returned an unexpected response. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: error: code: upstream_error message: Failed to fetch scheduled posts. Try again shortly. AccountsUnavailable: description: >- Linked-account verification is temporarily unavailable (fail closed). The main account keeps working. content: application/json: schema: $ref: '#/components/schemas/ErrorEnvelope' example: error: code: accounts_unavailable message: >- Account information is temporarily unavailable. Try again shortly. securitySchemes: apiKey: type: http scheme: bearer description: >- A SuperX API key ("sxk_..."), created in the SuperX app under Account > API / MCP / CLI. Keys are server-side secrets. ````