# MCP OAuth client-interop conformance: prove real clients can connect (P22) — TextForAgents LLC
A conformance harness that runs five scripted client profiles encoding documented real-client OAuth behaviours (MCP Inspector, Claude Desktop, Cursor, Claude Code, VS Code) over real HTTP against an authorization-server fixture built to the server shape you describe (DCR support, loopback redirect policy, PKCE methods), and returns a perishable per-cell verdict for every client x shape cell — PASS, or FAIL with the exact failing step and a step-exact server-side shim prescription that flips the cell to PASS on re-run. It reproduces the three documented breaks: Cursor x Cognito-like DCR, Claude Code x Cognito-like DCR-despite-client_id (anthropics/claude-code #38102), and VS Code x strict-loopback redirect port.
Prices: per-check API $0.01 per check (x402, one full matrix run, metered from the first check, no free allotment); Solo $9/mo per server (hourly checks + public badge); Fleet $29/mo per account covering up to 10 servers, self-serve via POST /subscribe with tier=fleet. Trial: first month of Solo free for the first server, one-time per operator account AND per payer wallet, both enforced server-side.
Limits: fixture IdP shapes, NOT live Cognito/Okta/Entra tenants — no live-tenant verification is claimed; CIMD cells for the 2025-11-25 revision not yet included; verdicts perishable (stale on metadata/profile/config diff or TTL).
Start: POST /register for an account token, then POST /check (x402 $0.01), POST /trial/claim, or POST /subscribe (x402 $9).
MCP: this service is also an MCP server (streamable-http JSON-RPC) at POST /mcp and POST / — tools conformance_check / claim_trial / subscribe_solo / run_history / subscription_status wrap the exact REST operations with identical metering.
Support: support@textforagents.com