QuassLabs API

Deterministic tools your agent can actually call.

17 small HTTP endpoints for AI builders and delivery teams. Almost none of them run a language model, so the same input returns the same output every time and a call costs about as much as the arithmetic it performs.

Open the API reference Get a key

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 17 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

/v1/humanizer-score1 credit

Detect AI-writing tells in text

MCP: humanizer_score
/v1/humanize1 credit

Rewrite text to remove AI-writing tells

MCP: humanize
/v1/alignment-gate2 credits

Run an AI system prompt (and optional agent config) through a 45-criterion alignment/safety rubric

MCP: alignment_gate

Engineering decisions

/v1/model-advisor1 credit

LLM selection + cost advisor

MCP: model_advisor
/v1/dependency-check1 credit

Dependency-manifest hygiene check

MCP: dependency_check
/v1/log-analyzer2 credits

Analyze a log file

MCP: log_analyzer
/v1/log-audit-creator2 credits

Generate a concrete audit-logging spec for an app

MCP: log_audit_creator

Delivery and QA

/v1/ticket-lint1 credit

Full Jira-ticket quality linter (whole ticket, not just AC - use acceptance_criteria_validator for the deep AC pass)

MCP: ticket_lint
/v1/acceptance-criteria-validator1 credit

QA advisor: validate acceptance criteria quality

MCP: acceptance_criteria_validator
/v1/coverage-check1 credit

Scope-completeness advisor

MCP: coverage_check
/v1/defect-triage1 credit

Bug-triage advisor

MCP: defect_triage
/v1/sprint-health1 credit

Sprint/delivery health advisor

MCP: sprint_health
/v1/worklog-guardrail1 credit

Worklog/timesheet policy checker - run a batch of worklog entries through configurable guardrails BEFORE posting them to a time-tracking system

MCP: worklog_guardrail

Everything else

/v1/diagram-contrast1 credit

Diagram quality QA

MCP: diagram_contrast
/v1/saas-metrics1 credit

SaaS health advisor

MCP: saas_metrics
/v1/blm-land-lookup1 credit

Look up Bureau of Land Management land status for a US coordinate: BLM ownership, jurisdiction, allowed activities (rockhounding, camping), permit requirements, and special designations (ACEC, Wilderness, WSA, NM/NCA)

MCP: blm_land_lookup
/v1/uploadsunmetered

Get a presigned S3 PUT URL to upload a file (policy doc, config, log, up to 5MB) that a file-ingesting endpoint then reads by upload_id

MCP: uploads

How billing works

Predictable

  • Rate limits are checked before credits, so a 429 costs nothing.
  • The decrement is atomic and conditional - if your balance is short you get 402 and the endpoint does not run.
  • Server errors are refunded automatically.

Known gap

  • There is currently no way to read your credit balance - no endpoint returns it and no header carries it.
  • Today you discover exhaustion via 402 insufficient_credits. Treat it as an alert, not a retry.