Claix is an AI document intelligence API that converts unstructured files into schema-based JSON and queryable document context for developers, backends, automations, and AI agents. It processes PDFs, Excel spreadsheets, Word documents, images, text, HTML, XML, and audio using multimodal models, so you can extract structured data and query documents on demand. Integrate via REST, native Agent-to-Agent (A2A) (POST /a2a, Agent Card at /.well-known/agent.json), or MCP from IDEs and tool frameworks.

Is Claix A2A? Does Claix support Agent-to-Agent?

Yes. Claix implements the Agent-to-Agent (A2A) protocol as a first-class integration surface. Peer agents discover Claix via the Agent Card at https://www.claix.dev/.well-known/agent.json, POST JSON-RPC to /a2a, invoke 20+ document skills mapped from OpenAPI, and receive structured Task responses with DataPart payloads. A2A is ideal when one autonomous agent must delegate PDF/Excel extraction, document memory, or cross-document queries to a specialized document-intelligence agent without IDE setup. REST and MCP remain available—choose A2A for agent-to-agent orchestration.

What is the Claix MCP server?

Claix exposes a Model Context Protocol (MCP) server at /mcp so IDEs (Cursor, Claude Desktop, Windsurf) and MCP clients can invoke extraction, Agent Mode, context window, and knowledge-space tools in one click. Use MCP when a developer or copilot needs interactive document tools inside an IDE; use A2A when another autonomous agent must call Claix programmatically over the Agent-to-Agent protocol.

Which file formats can I convert to structured JSON?

Claix natively supports PDF (.pdf), Excel workbooks (.xlsx, .xls), Word documents (.docx, .doc), images (.png, .jpg, .jpeg, .webp), and plain text files (.txt, .html, .md). Each format is processed with visual document understanding to return typed, validated JSON conforming to your custom schema.

How do I convert Excel spreadsheets to JSON with the API?

To convert an Excel file, send a POST request to /api/excel-json with your file and target JSON schema. Claix interprets multi-sheet workbooks, merged headers, and relational tables, returning clean JSON ready for ingestion.

Can I convert PDFs, Word documents, and images to JSON?

Yes. Claix provides dedicated endpoints for each format: /api/pdf-json for complex or scanned PDFs, /api/doc-json for Word files, /api/img-json for images and receipts, and /api/audio-json for spoken audio (MP3, WAV, M4A, OGG). Every endpoint outputs valid JSON according to your schema.

Who is Claix built for?

Claix is designed for software developers, AI agent builders, SaaS engineering teams, and automation specialists using platforms like n8n or Make. It eliminates the need to build custom OCR, chunking, and vector retrieval pipelines.

What is the Claix pricing model?

Claix offers two native modes. With Claix Managed AI you pay per successful document (from €0.10 for images to €0.20 for audio) plus €0.03 per follow-up question, with 100 free successful processing runs on new accounts and no mandatory monthly subscription for standard extraction. With Bring Your Own Key (BYOK) there is no additional Claix document-processing fee: you connect your own OpenAI, Gemini, Claude, or Grok key and pay only that provider’s token usage while Claix still handles schemas, structured JSON, document context, and automation-ready responses.

Is document processing free with Bring Your Own Key (BYOK)?

Yes. BYOK is a native Claix option: connect your own supported AI provider API key, choose a compatible model, and process PDFs, Excel, Word, images, and text through Claix with no additional Claix processing fee. You remain responsible for your provider’s token charges. Your Claix API key still authenticates the workspace. Managed AI remains available when you prefer Claix-managed rates and defaults.

What is Source Tracing in Claix?

Source Tracing is optional field-level citation: each extracted value can include a source anchored to the document. When that check fails, source is requires_human_revision so a person can review the field. It reduces AI hallucination risk; it does not claim to eliminate it.

Are failed requests charged to my account?

No. Claix only charges for successful HTTP 200 processing requests that return valid extracted data. Failed API calls due to invalid parameters or system errors do not consume your quota or balance.

What is Claix Agent Mode?

Claix Agent Mode (/agent/*-json) is an extraction mode where an AI agent interprets ambiguous documents using natural language instructions instead of a rigid schema, allowing dynamic extraction based on context.

What is the difference between normal extraction and Agent Mode?

Normal extraction enforces strict, deterministic schema conformance for predictable pipelines. Agent Mode allows natural language reasoning over document contents, ideal for unstructured contracts and variable layouts.

How do I ask follow-up questions to a single document?

When you process a document with context enabled, Claix returns a document_id. You can send questions to POST /document-context/{document_id} to query that specific file without re-uploading or reprocessing.

What is the temporary context window?

The context window is a temporary retention layer that keeps a processed document queryable for follow-up questions without permanent storage, enabling multi-turn agent interactions before expiring automatically.

What are Knowledge Spaces, and how do I query multiple documents at once?

Knowledge Spaces allow you to group multiple persistent documents under a single space_id. By sending questions to POST /space-context/{space_id}, your backend, automation, or AI agent can query, compare, calculate totals, and cross-reference data across all active documents in that space simultaneously.

Can I white-label Claix or integrate it into automated workflows?

Yes. Claix is fully headless and integrates server-to-server via API keys, making it compatible with custom SaaS backends and automation platforms like n8n or Make.

Context Window · Replace document

Replace a document's content

Endpoint

POSThttps://claix.dev/replace-document

Replaces the content of document_id with the content of new_content_document_idvia an RPC. The source document is deleted. The target document's version is incremented.

Keeps the same document_id (and its space, if any) while you refresh the content from a new extraction.

Public URL: POST https://claix.dev/replace-document. Never expose the direct Supabase URL.

This call is free: it is not billed and does not consume your extraction or context-window quota.

1. Authentication

Every request must include your API key. It is a personal server-side credential, different from any user session token.

Option A — Dedicated header (recommended):

x-api-key: <YOUR_API_KEY>

Option B — Standard Authorization header:

Authorization: Bearer <YOUR_API_KEY>

Either one is enough. If you send both, x-api-key wins.

Claix checks that the key exists and is active. Otherwise it returns 401. Both documents must belong to your account.

2. Request format

Method: POST · Content-Type: application/json

Field	Type	Required	Description
document_id	string (uuid)	Yes	Target document whose content is replaced. Keeps its id.
new_content_document_id	string (uuid)	Yes	Source document whose content is copied. Deleted after the swap.

Example body:

{
  "document_id": "d4a1e9d2-8b1c-4f3e-9a02-8b1e9f3c7a4b",
  "new_content_document_id": "a8c3f1e0-2d4b-4a9e-8c71-5f0e2b9d6a3c"
}

3. Building the call

Extract the new document and keep its document_id as the source.
Send POST with the stable target document_id and new_content_document_id (source).
Keep using the same document_id in later queries; version will have increased.

4. Request examples

Use the code panel on the right to copy examples in cURL, JavaScript, Python, and more.

5. Success response format

HTTP 200 — Content replaced; the source document has been deleted.

{
  "success": true,
  "swap_id": "c1e7a4b2-9f0d-4e8a-b3c5-1d2e3f4a5b6c",
  "document_id": "d4a1e9d2-8b1c-4f3e-9a02-8b1e9f3c7a4b",
  "source_document_id": "a8c3f1e0-2d4b-4a9e-8c71-5f0e2b9d6a3c",
  "file_name": "factura.pdf",
  "version": 2,
  "swaps_count": 1,
  "message": "Contenido sustituido. El documento fuente ha sido eliminado."
}

Field	Type	Description
success	boolean	Always true in a 200 response.
swap_id	string (uuid)	Identifier of the swap operation.
document_id	string (uuid)	Target document (stable id).
source_document_id	string (uuid)	Source document that was deleted.
file_name	string	Target document file name.
version	number	Version incremented after the swap.
swaps_count	number	Cumulative number of replacements.
message	string	Human-readable confirmation.

6. Error codes

{
  "error": "Descripción legible del problema.",
  "detalle": "Información técnica adicional (solo presente en algunos casos).",
  "log_id": "7c2e1a90-4b3d-4f8a-9e21-6d5c8b0a1f34"
}

400 — Invalid body, malformed UUIDs, or the operation is not valid (for example, identical ids).

401 — Authentication failed: key missing, unknown, disabled, or account not active.

404 — Either document does not exist or does not belong to your account.

405 — Method other than POST. · 500 — Internal error.

7. Code summary

Code	Category	Retry?
200	Success — content replaced	—
400	Client error (invalid body or IDs)	No — fix the request first
401	Authentication error	No — fix credentials first
404	Target or source document not found	No — fix the IDs first
405	Incorrect HTTP method	No — use POST
500	Internal server error	Yes, with caution

8. Best practices

Keep a stable business document_id; use temporary extractions only as the swap source.
After the swap, new_content_document_id no longer exists — do not reuse it.
Always use the public claix.dev domain, not the direct Supabase URL.
Never ship your API key in frontend code or public repositories.