Deterministic tools your agent can actually call.

One call

Every endpoint is a POST with a JSON body. No query parameters, no path parameters, nothing to construct.

curl -sS https://api.quasslabs.com/v1/humanizer-score \
  -H "Authorization: Bearer qlk_YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text": "Let us delve into this transformative paradigm."}'

You get back a score, the band it falls in, and the exact patterns that fired with their positions - not an opaque number.

Or no calls at all

Every endpoint here is also an MCP tool. Point Claude, Claude Code, or any MCP host at one URL and the whole toolset appears natively - no client code, no tool definitions to maintain, and nothing to redeploy when we ship a new endpoint.

claude mcp add --transport http quasslabs https://api.quasslabs.com/mcp \
  --header "Authorization: Bearer qlk_YOUR_API_KEY"

Auth, rate limiting and credit metering behave exactly as they do over REST, and the gateway is not itself metered - going through MCP never costs more than calling directly. Connection details.

The 20 endpoints

Prices are per successful call. A rate-limited request is never billed, and anything that fails with a server error is refunded automatically.

Writing and prompts

Engineering decisions

Delivery and QA

Diagrams

Everything else

How billing works