# The Agent API — IgnatiusTheYoungerAI

> An API priced for agents, not people. Four paid endpoints at $0.50 a query over the Machine Payments Protocol, six free ones, and an MCP server. No account, no key, no sales call.

- canonical: https://ignatiustheyoungerai.com/api
- html: https://ignatiustheyoungerai.com/api
- machine-view: https://ignatiustheyoungerai.com/api?view=machine
- markdown: https://ignatiustheyoungerai.com/api.md
- site-index: https://ignatiustheyoungerai.com/llms.txt
- service-root: https://api.ignatiustheyoungerai.com
- openapi: https://api.ignatiustheyoungerai.com/openapi.json
- llms-txt: https://api.ignatiustheyoungerai.com/llms.txt
- mcp-server-card: https://api.ignatiustheyoungerai.com/.well-known/mcp.json
- agents-manifest: https://api.ignatiustheyoungerai.com/agents.json
- counters: https://api.ignatiustheyoungerai.com/v1/stats
- evidence-labels: RESEARCH · REPORTED · ANALYSIS · MODELED · RECOMMENDATION · OBSERVED — carry the label with the claim; MODELED is arithmetic from stated assumptions, never a measured outcome
- publisher: IgnatiusTheYoungerAI (Nathan Battin) · hello@ignatiustheyoungerai.com

---

Agent-facing infrastructure · Endpoints and prices read from the running service 2026-09-20

## What is being sold

**Forward Deployed Engineering rules.** Operating discipline for shipping and running systems. Every rule traces to a specific real incident and carries an implementable constraint on agent behaviour rather than general advice. Situational playbooks and a pre-ship checklist are sold alongside it.

**The Agent Pricing Index.** 47 AI products across seven categories. Every row was read off the vendor's own pricing page on the collection date and carries a verbatim evidence quote and a read date. Where a vendor publishes no price the field is null and the absence is recorded as the finding. No price is estimated, and none is carried over from an earlier snapshot.

36 of the 47 products gate their pricing behind a sales call. Nine publish no price at all. [OBSERVED 2026-09-20]

## Free endpoints

| Endpoint | Returns |
|---|---|
| `GET /v1/catalogue` | Every rule, playbook and checklist phase on offer, paid bodies withheld |
| `GET /v1/fde-lessons/preview` | The foundational engineering rules in full |
| `GET /v1/pricing/index` | Dataset descriptor, method statement and contribution schema |
| `GET /v1/pricing/aggregates` | Category medians, published only at five or more submissions per category |
| `GET /v1/stats` | Traffic and paywall counters |
| `POST /v1/pricing/submit` | Contribute a pricing row; individual submissions are never republished |

## Paid endpoints — $0.50 USD per query

| Endpoint | Returns |
|---|---|
| `GET /v1/fde-lessons` | The full ruleset, or the subset matching a topic |
| `GET /v1/fde-playbooks` | Situational runbooks with ordered, checkable steps |
| `GET /v1/fde-preship-checklist` | Every gate to clear before shipping, each with its concrete check |
| `GET /v1/pricing` | Every published row plus the derived comparables per category |

## How payment works

1. Call a paid endpoint with no payment attached.
2. Receive `402` with a `WWW-Authenticate: Payment` header carrying realm, method, amount and expiry. The price is learned here, which is why a first request is always unpaid.
3. Settle the challenge with a supported wallet over the Machine Payments Protocol.
4. Retry the same call with the credential attached. The response carries the payload and a receipt.

Settlement is over Stripe card rails. A receipt accompanies every paid response.

## MCP server

`POST /mcp`. Free tools answer directly. Paid tools return the payment challenge in band under the `org.paymentauth/payment-required` metadata key, so a client can detect the charge and settle it without leaving the protocol.

| Tool | Price |
|---|---|
| `fde_catalogue` | Free |
| `fde_lessons_preview` | Free |
| `fde_lessons_full` | $0.50 |
| `fde_playbook` | $0.50 |
| `fde_preship_checklist` | $0.50 |

## On the counters

`/v1/stats` is directional. Eventually consistent, self-reported client class, not an accounting record. Stripe is the ledger for revenue. It is published because a service that asks to be trusted with a paywall should show what arrives at it.

## What has been retired

A WARN Act layoff feed shipped on this rail and was withdrawn from sale on 2026-09-18. A free, Apache-2.0, 47-state register reached freshness parity with our three states. Its three paths answer `410 Gone` with a body naming the register, its licence and its CSV URL.

Recorded rather than deleted. Public-record data commoditises to zero the moment open scrapers meet a cron; judgment-made data does not.