Experiment 01 · live deterministic API
Useful work
before payment.
A small public surface where software agents and human developers can discover, test, and eventually purchase deterministic Checklist Assistant operations without guessing what a model might do.
01 / Service
A narrow, honest surface.
Submit Checklist Markdown. The production CHAX parser returns exact Slug IDs, canonical Markdown, row structure, and actionable validation errors without persisting the submitted content.
Inspect
POST /api/v1/checklist/inspect with text/markdown.
Quote
POST /api/v1/checklist/canonicalize/quote measures whether a draft fits the candidate Checklist Pass. It does not charge or persist.
02 / Live probe
Ask the real parser.
The sample stays transient. This browser sends it to the same public, non-persisting inspection path described by the API contract.
Run the probe to see the production response.
Direct clients can use the same endpoint. Request and response details are versioned in openapi.json.
03 / Pricing hypothesis
Free discovery. Paid evidence.
These are experiment targets, not active charges. The first paid route will go live only after settlement, refunds, receipts, and accounting are tested end to end.
Capability
State
Target
Schema and service discovery
Live
$0
Non-persisting Checklist Markdown inspect
Free pilot
$0
Checklist Pass: 8 iterations in 24h, up to 64 KiB / 16 procedures, one final receipt
Candidate
$0.01 / pass
Validated relationship and report artifact
Candidate
Price after measurement
Machine-readable version: pricing.json. The signed-in Payment Lab exercises Stripe sandbox payments and refunds; no active endpoint currently requests real money.
04 / Protocol posture
Claims match the wire.
Discovery documents describe only what a client can call today. Protocol names move to “live” only after their required transport, security, and transaction flows pass publicly.
HTTPS + OpenAPI
A callable deterministic REST operation with an explicit input and response contract.
LLM-readable index
A compact map for machine clients, with billing state stated rather than inferred.
x402
Requires an approved merchant rail or receiving wallet, replay-safe fulfillment, receipts, and tested refunds.
MCP + A2A
CHAX has a local MCP bridge. A public remote server and A2A endpoint are not advertised until they implement the current specifications.
05 / Economic evidence
The receipt should explain the work.
A future paid response should bind buyer authorization, request hash, checklist identity, engine version, outcome, artifact hash, price, settlement reference, and time. That makes payment an auditable procedural event instead of a disconnected transaction.