Error Codes

All OutX API errors return a JSON object with an error field containing a human-readable message.

{
  "error": "Error message here"
}

400, Bad Request

Missing or invalid parameters. Check the error message for specifics. Watchlist endpoints:

Error Message	Cause
`Either keywords array or prompt string is required`	Keyword/Reddit watchlist create with neither mode supplied
`Provide either keywords or prompt, not both`	Keyword/Reddit watchlist create with both modes at once
`keywords array is required and must not be empty`	Watchlist update: `keywords` passed but empty or not an array
`No valid keywords provided after cleaning`	All keywords are invalid/empty after normalization
`profiles array is required and must not be empty`	People watchlist: `profiles` missing, not an array, or empty
`No valid profile identifiers provided`	No profiles passed validation
`companies array is required and must not be empty`	Company watchlist: `companies` missing, not an array, or empty
`No valid company identifiers provided`	No companies passed validation
`Invalid fetchFreqInHours`	Must be one of: 1, 3, 6, 12, 24, 48, 72
`Missing required parameter: id`	Watchlist update/delete called without `id`
`Name cannot be empty`	Watchlist update with empty name
`No valid update fields provided`	Watchlist update with nothing to change
`disable must be a boolean value`	Watchlist enable/disable with invalid value
`watchlist_id is required and must be a string`	Get Posts / Get Interactions without a `watchlist_id`
`Invalid watchlist ID: <id>`	Get Posts / Get Interactions: `watchlist_id` doesn’t exist
`Unknown query parameter(s): ...`	Get Posts: an unrecognized parameter was sent, e.g. `limit`, `offset`, `per_page`, or `pageSize` instead of `page`/`page_size`. The message lists the offending names, a did-you-mean suggestion where the alias is close enough to an accepted name (`limit -> page_size`, `pageSize -> page_size`, `offset -> range_from`; `per_page` gets no specific hint), and all accepted parameters in every case.
`Invalid value(s) for <param>: ...`	Get Posts: `sort_by`, `relevance_level`, or `seniority_level` got a value outside its allowed set. The message lists the allowed values.

Engagement endpoints:

Error Message	Cause
`Missing required parameter: post_id`	Like/comment without `post_id`
`Missing required parameter: user_email`	Like/comment without `user_email`
`Missing required parameter: comment_text`	Comment without `comment_text`
`comment_text cannot be empty`	Comment with empty or whitespace-only text
`Invalid actor_type. Must be 'user' or 'company'`	`actor_type` not `"user"` or `"company"`
`company_title is required when actor_type is 'company'`	Engaging as company without providing company name
`Post does not support like functionality (missing social_urn)`	Post has no activity URN (may be deleted)
`Post does not support comment functionality (missing social_urn)`	Post has no activity URN (may be deleted)

LinkedIn Data endpoints:

Error Message	Cause
`Missing or invalid 'profile_slug'`	`fetch-profile` without a valid `profile_slug` string
`Missing or invalid 'profile_urns' (must be a non-empty array)`	`fetch-profiles-posts` without a valid array of URNs
`Missing or invalid 'social_urn'`	`like-post` or `comment-post` without a valid `social_urn`
`Missing or invalid 'comment_text'`	`comment-post` without a valid `comment_text`
`Missing or invalid 'api_agent_task_id'`	`get-task-status` without a valid task ID
`Missing or invalid 'email'`	Auth endpoints without a valid email
`Missing or invalid 'otp'`	`auth-verify-otp` without a valid OTP code

401, Unauthorized

API key is missing or invalid.

Error Message	Cause
`Missing API Key`	No `x-api-key` header in the request
`Invalid API Key`	The API key does not match any team
`Invalid or expired OTP`	OTP code is incorrect or has expired (auth-verify-otp)

Fix: Include your API key in the x-api-key header. Get your key at mentions.outx.ai/api-doc.

402, Plan Limit Reached

Your team has hit a plan-based limit. The error message includes your current limit.

Error Message Pattern	Cause
`Your plan includes up to N watchlists...`	Watchlist count limit reached
`Your plan includes total of N likes...`	Daily like limit reached (resets at UTC midnight)
`Your plan includes total of N comments...`	Daily comment limit reached (resets at UTC midnight)
`Your plan includes total of N company trackings...`	Company tracking limit reached
`Your plan includes total of N team members...`	Team member invitation limit reached
`Your plan allows up to N posts per week per watchlist...`	Weekly post fetch limit per watchlist reached
`Your plan allows up to N active AI agents per watchlist...`	Auto-engagement rule limit per watchlist reached

Fix: Upgrade your plan at outx.ai/pricing or wait for daily/weekly limits to reset.

Plan limits by tier:

Free: 2 watchlists, 1 auto-engagement rule per watchlist, 5 team members
Pro: 5 watchlists, 2 auto-engagement rules per watchlist, 10 team members
Expert: 20 watchlists, 5 auto-engagement rules per watchlist, 25 team members
Ultimate: 100 watchlists, 10 auto-engagement rules per watchlist, unlimited team members

403, Forbidden

Access denied. Most commonly caused by the Chrome extension not being active.

Error Message	Cause
`Plugin installation required: Please install the OutX browser extension on at least one team member's account to use the API. The plugin must have been active within the last 48 hours.`	No team member has an active Chrome extension
`Access denied: You don't have permission to access this resource`	Trying to access another team’s resources
`Access denied: You don't have permission to access these watchlists`	Trying to access watchlists from another team
`Access denied: You don't have permission to interact with this post`	Trying to engage with a post from another team’s watchlist

Fix for plugin error: Install the OutX Chrome extension, sign into LinkedIn in the same browser, and keep the browser open. The extension must have been active within the last 48 hours. See Chrome Extension Guide.

The 403 plugin error is the most common API issue. If you’re getting this error, check that:

The Chrome extension is installed on at least one team member’s browser
That browser has been open within the last 48 hours
The team member is signed into LinkedIn in the same browser

404, Not Found

The requested resource does not exist or belongs to a different team.

Error Message	Cause
`Agent task not found`	LinkedIn Data task ID does not exist or belongs to another team
`Watchlist not found or access denied`	Watchlist ID does not exist, isn’t the requested type (keyword/reddit/people/company), or belongs to another team. Returned on GET, PUT, and DELETE. Note: each endpoint only sees its own type, so asking `/api-keyword-watchlist` for a Reddit watchlist’s ID returns 404.
`List not found or access denied`	Creating watchlist with a `list_id` that doesn’t exist
`Post not found`	The `post_id` in a like/comment request does not exist
`Tracking list not found`	The post’s associated watchlist no longer exists
`User not found with email: [email]`	The `user_email` is not a member of your team
`Company not found`	The `company_title` does not match any company page for the admin user
`No admin user found in the team`	LinkedIn Data engagement, your team has no admin members
`No company admin found for the specified company`	No admin user manages the specified company page

409, Conflict (Disabled Watchlist)

{
  "error": "This watchlist is disabled. Enable it before updating it."
}

You sent a PUT /api-keyword-watchlist or PUT /api-reddit-watchlist (patch mode or prompt mode) against a paused watchlist. A disabled watchlist rejects updates so a paused list cannot be silently mutated or backfilled. Fix: Re-enable first, then retry the update:

curl -X PUT "https://api.outx.ai/api-keyword-watchlist" \
  -H "Content-Type: application/json" \
  -H "x-api-key: YOUR_API_KEY" \
  -d '{ "id": "YOUR_WATCHLIST_ID", "disable": false }'

Check whether a watchlist is disabled via the disabled field on the type’s GET endpoint (GET /api-keyword-watchlist?id=... or GET /api-reddit-watchlist?id=...).

405, Method Not Allowed

{
  "error": "Method GET not allowed"
}

You used the wrong HTTP method. Check the endpoint documentation for the correct method (GET, POST, PUT, DELETE).

429, Rate Limit Exceeded

{
  "error": "Rate limit exceeded. Please try again later."
}

You have exceeded your plan’s API request quota. See Rate Limits for details and retry strategies.

500, Internal Server Error

An unexpected error occurred on our side. Retry with exponential backoff. If the error persists, contact support@outx.ai.

Error Response Format

Every error, on every endpoint, is a JSON object with a single error field:

{
  "error": "Human-readable error message"
}

There are no other error fields (no details, no code). Parse the HTTP status for the category and the error string for specifics.

Frequently Asked Questions

Why am I getting a 403 error even though my API key is correct?

The most common cause is the Chrome extension requirement. At least one team member must have the OutX Chrome extension installed and actively used within the last 48 hours. Install the OutX Chrome Extension, sign into LinkedIn in the same browser, and keep the browser open.

What does 'Plugin installation required' mean?

OutX retrieves LinkedIn data through real browser sessions via the Chrome extension. This error means no team member has had the extension active recently. The extension runs in the background, just keep Chrome open with the extension installed and it will stay active.

How do I fix a 402 plan limit error?

402 errors mean you’ve reached a limit on your current plan. You can either upgrade your plan at outx.ai/pricing, wait for daily/weekly limits to reset, or delete existing resources (like watchlists) to make room for new ones.

Do daily limits reset at a specific time?

Yes. Daily limits (likes, comments) reset at UTC midnight (00:00 UTC). Weekly limits (posts per watchlist) reset on Monday at 00:00 UTC.

Getting Started

Authentication (OTP)

Keyword Watchlist

People Watchlist

Company Watchlist

Reddit Watchlist

Posts & Engagement

Team & Usage

LinkedIn Data

Integrations

Error Codes

Error Codes

400, Bad Request

401, Unauthorized

402, Plan Limit Reached

403, Forbidden

404, Not Found

409, Conflict (Disabled Watchlist)

405, Method Not Allowed

429, Rate Limit Exceeded

500, Internal Server Error

Error Response Format

Frequently Asked Questions

​Error Codes

​400, Bad Request

​401, Unauthorized

​402, Plan Limit Reached

​403, Forbidden

​404, Not Found

​409, Conflict (Disabled Watchlist)

​405, Method Not Allowed

​429, Rate Limit Exceeded

​500, Internal Server Error

​Error Response Format

​Frequently Asked Questions

Error Codes

400, Bad Request

401, Unauthorized

402, Plan Limit Reached

403, Forbidden

404, Not Found

409, Conflict (Disabled Watchlist)

405, Method Not Allowed

429, Rate Limit Exceeded

500, Internal Server Error

Error Response Format

Frequently Asked Questions