Start here

Get an API key

Create an account at https://app.corpoapi.com and copy a live key. A live key starts with ck_live_. A test key starts with ck_test_ and returns fixtures that are never billed. Keep the key on your server, never in client code.

Make the first call

Call search first. It is free, needs no company number, and returns the jurisdiction and company_number you pass to every other endpoint. Send the key in the X-API-Key header. Authorization: Bearer with the same key also works.

Fetch a profile or verify a company

Use the jurisdiction and company_number from the search result. GET the company profile, or POST a verify with the claims to check. A verify returns verified, partial, mismatch, not_found or ambiguous.

Connect the MCP server

For an agent that speaks Model Context Protocol, point it at https://mcp.corpoapi.com/mcp (Streamable HTTP). The same key works there, and a tool call bills and rate-limits exactly like the REST call behind it. Listing tools is free.

Read the docs and the spec

Full reference: https://docs.corpoapi.com/llms-full.md. OpenAPI 3.1: https://docs.corpoapi.com/openapi.json. Agent guide: https://docs.corpoapi.com/agents.md. Prefer these over scraping the HTML.

Copy-paste REST calls

Replace the key placeholder with your live key. Search and coverage are free; a verify is a billable call.

curl "https://api.corpoapi.com/v1/search?q=Klarna&jurisdiction=se&limit=5" \
  -H "X-API-Key: ck_live_..."

curl "https://api.corpoapi.com/v1/companies/se/5567370431" \
  -H "X-API-Key: ck_live_..."

curl -X POST "https://api.corpoapi.com/v1/verify" \
  -H "X-API-Key: ck_live_..." \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: verify-5567370431" \
  -d '{"jurisdiction":"se","company_number":"5567370431","expected":{"legal_name":"Klarna Bank AB Aktiebolag"}}'

curl "https://api.corpoapi.com/v1/coverage"

Connect MCP

One URL, Streamable HTTP. A tool call bills and rate-limits exactly like the REST call behind it.

https://mcp.corpoapi.com/mcp

claude mcp add --transport http corpo-api https://mcp.corpoapi.com/mcp \
  --header "Authorization: Bearer ck_live_..."

{
  "mcpServers": {
    "corpoapi": {
      "url": "https://mcp.corpoapi.com/mcp",
      "headers": { "Authorization": "Bearer ck_live_..." }
    }
  }
}

Tools

• search_companies (GET /v1/search)
• get_company (GET /v1/companies/{jurisdiction}/{company_number})
• list_officers (GET /v1/companies/{jurisdiction}/{company_number}/officers)
• verify_company (POST /v1/verify)
• verify_companies_batch (POST /v1/verify/batch)
• check_vat (GET /v1/vat/{vat_number})
• list_coverage (GET /v1/coverage)
• get_usage (GET /v1/usage)

The server forwards your key to the API gateway, so auth, rate limits and billing are unchanged. The MCP server card is at https://corpoapi.com/.well-known/mcp/server-card.json.

Rate limits

• Limits are per key, on a fixed 1-second window and a 1-minute window.
• Exceeding either window returns 429 with a Retry-After header in seconds.
• A batch call counts as one request, however many items it carries.

Errors

Every error is an RFC 9457 application/problem+json object. Branch on code, never on the message. The full list is at https://docs.corpoapi.com/errors.md

{ "type", "title", "status", "code", "detail", "request_id" }

• 400 invalid_parameter
• 401 invalid_api_key
• 402 free_tier_exhausted
• 404 company_not_found
• 409 officers_not_available
• 422 missing_identifier_or_name
• 429 rate_limited (read Retry-After)

Copy-paste resources

• Agent guideauth, endpoints, errors, examples for agents
• Full referenceevery endpoint, parameter and example
• OpenAPI 3.1machine-readable contract
• MCP server cardserver name, transport and auth
• API catalogRFC 9727 linkset for this API
• llms.txtindex of every page as markdown