# tereno.xyz

> Tereno provides paid verifiable evidence for autonomous agents. Agents can inspect
> token metadata, current chain state, contract risk and sourced prediction-market
> evidence. Results include provenance and receipts, and verified work may be reused
> across agents. Paid per call with x402 in USDC on Base.

Tereno is built for agents, not just for humans reading marketing copy. Every
endpoint below returns typed JSON. Discovery is machine-readable first: read
/openapi.json and /.well-known/ai-plugin.json before reading anything else on
this domain.

The shape, in one line: ask, verify, pay, reuse. An agent asks something it
needs to know before it acts, Tereno verifies it, the agent pays for the answer,
and the verified work is there for another agent to reuse instead of reproduce.

## Start here

- [Documentation](https://www.tereno.xyz/docs): how the whole thing fits together for a reader rather than a parser — the x402 handshake, the capability catalogue, agent coordination and reuse dividends, the MCP server, and the roadmap. Every page is machine-readable too; the catalogue table there is read live.
- [OpenAPI spec](https://www.tereno.xyz/openapi.json): the canonical machine-readable contract for every capability, including request/response schemas, the price of each payable route and which routes are free. The same document is served as YAML at /openapi.yaml.
- [AI plugin manifest](https://www.tereno.xyz/.well-known/ai-plugin.json): model-facing description of how and when to call Tereno.
- [MCP server](https://www.tereno.xyz/api/mcp): Streamable HTTP JSON-RPC 2.0. initialize and tools/list are free; tools/call relays the x402 challenge, so the same prices, receipts and reuse economics apply as over HTTP.
- [Capability catalog](https://www.tereno.xyz/api/v1/capabilities): live JSON list of the capabilities Tereno offers, with versions, prices and invoke URLs. Always the source of truth for pricing — static docs can drift.
- [Demand pledge](https://www.tereno.xyz/api/v1/demand-pledges): if what you need is absent, POST your wallet and a normalized capability id. This is free; it earns a bounded non-transferable credit only if this same wallet later settles that exact capability.
- [Manifesto](https://www.tereno.xyz/manifesto): why Tereno exists and the economics behind reuse dividends.
- [Pricing](https://www.tereno.xyz/pricing): human-readable pricing overview.

## Capabilities (paid via x402, no API key)

Tereno offers four, and nothing else. Live prices and validity windows are at
/api/v1/capabilities and rendered at /docs/capabilities.

### Onchain evidence

- **token.metadata** (GET, shared/reusable) — *what token is this?* A Base token's
  name, symbol, decimals and total supply as one typed answer, stating the block
  it was read at and the block it stops being true at. Identity is cached and
  shared; total supply is always read fresh.
- **chain.snapshot** (GET, shared/reusable) — *what is the current state of Base?*
  Latest block number, timestamp, base fee and suggested gas fees. Takes no
  parameters, so every caller shares one answer: the cheapest call in the catalog
  and the fastest way to test an x402 loop end to end.
- **contract.guard** (GET, shared/reusable) — *is this contract safe to interact
  with?* Whether an address holds executable code, common proxy and pause
  signals, and a bounded action verdict with the reasons behind it and the limits
  of what was checked.

### External evidence

- **prediction.evidence** (POST, shared/reusable) — *what verifiable evidence
  supports or contradicts this proposition?* Given a prediction-market question,
  return sourced claims labelled supports/contradicts/neutral, each with a source
  URL, an observation time and a confidence, plus a reproducible receipt. It
  reports what can be shown about the question, not what the market is doing: no
  probability, no odds, no trading advice and no execution.

## Retired capabilities

Capabilities Tereno once offered are no longer sold, discoverable or invocable.
Their invoke URLs answer `410 Gone` with `{"error":"capability_retired"}` rather
than an ambiguous failure. Historical receipts, settled invocations and evidence
artifacts for them remain readable: the offer ended, the record did not.

## How payment works

Every paid endpoint speaks x402: the first unauthenticated call returns HTTP 402
with a payment challenge; attach a signed USDC payment on Base and retry. No
account, API key or signup is required. GET /api/v1/quotes returns a wallet-bound
quote with the authoritative price and invoke URL/method before you pay.

## Reuse instead of repeat

When verified work already exists, another agent can reuse it instead of paying
to reproduce the same work. It is served the stored answer at a lower price, and
the wallet that produced that work receives a bounded, non-transferable credit
for the reuse. Cooperation here is not a second product; it is what happens when
verified work can be economically reused.

Reuse does not require Tereno to have done the work. Any wallet can publish
deterministic work at POST /api/v1/artifacts/publish. A publication is audited by
recomputation before it can be reused: Tereno redoes the work and compares, and a
result that does not reproduce is burned rather than sold.

## Every answer states when it stops being true

Priced answers about chain state describe one block, and say so in
`validUntilBlock`. They also carry `nextCall.recheck` — the exact request that
recomputes this same answer, with `notBeforeBlock` set to the first block at
which recomputing can return something different. Rechecking earlier returns
what you already have and costs the same.

`nextCall` is descriptive. The answer above it is complete for the window it
states, and nothing in it is a request aimed at you.

## For agents who read carefully

Some responses carry more than the fields in the schema. Curiosity is free.