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Engineering · Document Processing

The Fastest Way to Implement AI Document Processing for Developers

Implement AI document processing fast with Claix. Turn PDFs, Excel, Word files, images, HTML and XML into structured JSON with 100 free calls or free BYOK.

The fastest path for developers

Most teams start document automation with a familiar stack: extract text, call an LLM, parse the response, fix types, and hope the output is stable next week. That path looks fast on day one and slows down every week after.

Claix compresses the stack into one developer-friendly step:

Define schema
    ↓
POST document + schema_id
    ↓
Receive typed JSON
    ↓
Save to database, CRM, ERP, or automation

You do not maintain regex for every vendor layout, rewrite prompts when a model updates, or build a separate validation layer for missing fields. The schema is the contract. Claix returns data that matches it.

Why document processing usually feels slow

Document automation breaks down for predictable reasons:

  • OCR gives text, not business fields. You still need logic to decide which number is the invoice total.
  • Raw LLM calls require prompt maintenance, token-heavy PDF uploads, and manual JSON cleanup.
  • Template-based parsers fail when a supplier changes wording, column order, or page layout.
  • Each format becomes a separate integration: one path for PDF, another for Excel, another for images.
  • Production workflows need null handling, type safety, and repeatable output — not paragraphs from a chat window.

Claix is built to remove those layers. One API, one schema, structured output across formats.

Formats supported out of the box

You should not need a different architecture for every file type your workflow receives.

InputEndpoint patternTypical use
PDF/api/pdf-jsonInvoices, contracts, forms, scanned documents
Excel / CSV/api/excel-jsonSupplier lists, pricing sheets, bulk imports
Word / text/api/doc-jsonContracts, reports, HR documents
Images/api/img-jsonReceipts, photographed forms, ID cards
HTML/api/html-jsonWeb pages, email exports, rendered content
XML/api/xml-jsonSystem exports, structured business feeds

The same schema can drive multiple endpoints. Your invoice workflow can accept a PDF from email, an Excel attachment from finance, or a photographed receipt without rewriting the downstream logic.

Integration speed: first call in minutes

A production-ready integration usually needs four steps:

  • Create a Claix workspace and copy your API key.
  • Create a schema with the fields your workflow needs.
  • Send a document with schema_id.
  • Map the JSON response into your system.

Example request:

curl -X POST https://www.claix.dev/api/pdf-json \
  -H "x-api-key: YOUR_CLAIX_API_KEY" \
  -F "file=@invoice.pdf" \
  -F "schema_id=YOUR_SCHEMA_ID"

The response is JSON aligned to your schema — ready for PostgreSQL, Supabase, a CRM, an ERP, or an n8n node without intermediate parsing code.

Invoice extraction example

An accounts-payable workflow often needs the same fields regardless of supplier layout:

invoice_number
supplier_name
invoice_date
due_date
total_amount
currency
tax_amount
purchase_order_number

Claix returns:

{
  "invoice_number": "INV-2026-00456",
  "supplier_name": "Example Supplies Ltd",
  "invoice_date": "2026-03-14",
  "due_date": "2026-04-13",
  "total_amount": 1284.5,
  "currency": "EUR",
  "tax_amount": 224.5,
  "purchase_order_number": "PO-2049"
}

Your automation can compare totals against a purchase order, route mismatches to finance, and approve matching invoices without a human copying numbers from a PDF.

Invoice PDF arrives
    ↓
Claix extracts typed fields
    ↓
Validate required values
    ↓
Match purchase order in ERP
    ↓
Approve, reject, or send to review

Schema-first beats prompt-first

Prompt-first document processing puts the contract in natural language. That works for experiments. In production, the contract belongs in a versioned schema.

Prompt-firstSchema-first with Claix
Output shape changes with wording and model updatesOutput shape is defined by schema_definition
Developers maintain long prompts per document typeDevelopers maintain one schema per workflow
Missing fields may be invented or omitted silentlyMissing fields return null with predictable structure
Hard to test across vendors and layoutsSame schema works across PDF, Excel, Word, and images
Types are validated manually after the callJSON arrives typed for numbers, dates, booleans, and arrays

Schema create, list, and delete operations are free. You iterate on structure before you scale document volume.

Built for developers, not ops inboxes

Claix is infrastructure for products and automations, not a mailbox where someone forwards PDFs for manual review.

  • REST API with predictable HTTP responses
  • schema_id as the stable contract between services
  • Embeddable white-label widget for customer-facing uploads
  • MCP server and agent endpoints for tool-calling workflows
  • Webhooks and automation platform support
  • Document evaluation against expected field values

That means your backend, SaaS feature, or AI agent can treat document extraction like any other API dependency — with a schema, not a prompt notebook.

Fast n8n integration

n8n teams often start with text extraction and a Code node full of regex. That breaks when a template changes. The faster pattern is binary in, JSON out.

Email / Webhook / Drive trigger
    ↓
Download attachment as binary
    ↓
HTTP Request to Claix with schema_id
    ↓
Map JSON fields in next node
    ↓
Update CRM, database, or notify on exceptions

No 500-line Code node. No parseInt chains for dates. When the supplier changes the invoice layout, the schema still defines what your workflow needs.

Avoid model lock-in

Document processing should not force you into one AI vendor forever. Claix separates the document layer from the model layer.

  • Use Claix Managed AI when you want the simplest default setup.
  • Use BYOK to connect OpenAI, Gemini, Claude, Grok, or another supported provider key.
  • Switch models without rewriting your downstream JSON mapping.
  • Keep schema_id as the stable interface for your app and automations.

Your workflow depends on field names and types, not on a single provider’s prompt format.

Cheap to start, predictable at scale

Speed matters, but so does cost control while you build. Claix gives you two clear paths:

OptionBest forHow billing works
100 free callsPrototyping and first production validationFirst 100 successful HTTP 200 document calls are free on Managed AI
Claix Managed AITeams that want zero key managementFlat per-call pricing on successful extractions
Bring Your Own Key (BYOK)Teams with existing provider accounts and cost targetsNo additional Claix processing fee; provider bills token usage

Claix does not charge an additional processing fee for BYOK. Customers remain responsible for their AI provider’s token usage and provider charges.

Compared with building and maintaining OCR plus LLM middleware yourself, a schema-first API usually saves engineering time within the first workflow — before you count ongoing prompt and parser maintenance.

Reduce implementation time

Teams move faster with Claix because the repetitive work is already handled:

  • No custom PDF text extraction pipeline
  • No prompt versioning per document vendor
  • No hand-written JSON parsers in application code
  • No separate OCR service for scanned documents
  • No one-off scripts per file format
  • No re-uploading the same document for every follow-up question

You define the fields once, connect the API once, and reuse the same output across backend services, customer portals, and automation tools.

Document Context: ask follow-up questions without reprocessing

After a document is processed, Claix can keep it available as document context. That lets you ask focused questions later without sending the full file again.

  • What payment terms are listed on this invoice?
  • Does this contract include an automatic renewal clause?
  • What is the termination penalty in section 8?
Process document once
    ↓
Keep context available
    ↓
Ask targeted questions when needed
    ↓
Receive structured answers without re-uploading the PDF

That reduces token waste, repeated processing, and brittle prompt chains in agent workflows.

Knowledge Spaces for multi-document workflows

Some tasks need more than one file. Reconciliation, contract review, and supplier audits often span invoices, purchase orders, pricing sheets, and agreements.

Contract
    + invoices
    + purchase orders
    + pricing sheet
        ↓
Knowledge Space
        ↓
Cross-document question or comparison

Example questions:

  • Which invoice does not match the agreed contract price?
  • What is the total billed by this supplier across all documents?
  • Which agreements renew in the next 90 days?

Knowledge Spaces turn document collections into queryable context for agents and automations — without building a custom vector pipeline for every project.

Comparison: common approaches vs Claix

ApproachTime to first working extractionProduction stabilityBest fit
DIY OCR + regexDays to weeksBreaks on layout changesFixed templates only
Raw LLM with promptsHoursDrifts with model and prompt changesExperiments and one-offs
No-Code mailbox parsersHoursHard to embed in your productLow-volume internal ops
Claix schema-first APIMinutes to hoursSchema is the stable contractProducts, agents, and production automations

When Claix is the right fit

Claix is a strong choice when:

  • You need PDF, Excel, Word, or image data in structured JSON fast
  • Your backend, CRM, ERP, or agent expects typed fields — not free text
  • You want to ship document automation without maintaining parsers
  • You need n8n, Make, Zapier, or custom API integration
  • You want to start with 100 free calls or control cost with BYOK
  • You need follow-up questions or multi-document analysis without rebuilding context each time

Claix is less ideal when your only goal is indexing large document libraries into a vector store for a generic chatbot. For executable business data in production workflows, schema-first extraction is usually the faster path.

Start in four steps

  • Create a Claix workspace and copy your API key.
  • Create a schema with POST /api/create-schema.
  • Send your first PDF, Excel file, or image with schema_id.
  • Wire the JSON response into your database, automation, or agent.

Frequently asked questions

What is the fastest way to implement AI document processing?
Define a schema, send the document to Claix with schema_id, and map the typed JSON response into your system. That avoids building separate OCR, prompt, and parsing layers.
How fast can I integrate Claix into my app?
Most developers send a first successful extraction in minutes: create a schema, make one HTTP POST with the file and schema_id, and use the JSON response.
Does Claix support PDF, Excel, Word, and images in one workflow?
Yes. Claix exposes format-specific endpoints, but the same schema can drive multiple input types so downstream logic stays unchanged.
Can I use Claix for free while building?
Yes. The first 100 successful HTTP 200 document calls are free on Managed AI. You can also use BYOK to avoid an additional Claix processing fee and pay only your provider’s token usage.
What does BYOK cost with Claix?
Claix does not charge an additional processing fee for BYOK. Customers remain responsible for their AI provider’s token usage and provider charges.
Can I avoid vendor lock-in to one AI model?
Yes. BYOK lets you connect supported provider keys and change models while keeping the same schema and JSON mapping in your application.
Can I use Claix with n8n?
Yes. Pass the attachment as binary to Claix in an HTTP Request node, receive structured JSON, and map fields directly into database or CRM nodes.
Is Claix only for one-time extraction?
No. Document Context supports follow-up questions on a processed file, and Knowledge Spaces support questions across related documents.

Final summary

The fastest way to implement AI document processing for developers is not more prompts — it is a schema-first API that returns typed JSON from PDFs, Excel files, Word documents, images, HTML, and XML in one integration path.

Claix lets you start with 100 free calls, scale with Managed AI, or use BYOK for provider flexibility without an additional Claix processing fee. Document Context and Knowledge Spaces extend that same API into follow-up and multi-document workflows.

If you need invoice extraction, contract fields, spreadsheet cleanup, or automation-ready document data, define your schema, send your first file, and ship the JSON where your product already lives.