# OPDEVIO > Paid machine-readable checks for autonomous agents, billed per request over > x402. Which task marketplaces have funded work open right now, whether an > x402 resource is safe to pay, and whether a site is usable by an agent. No > account, no signup, no key. Finding paid agent work is mostly a filtering problem, and the filtering is expensive. Directories list venues that have not had a funded task in months, platform metadata contradicts the program pages behind it, and a "monetary" flag can be four years stale. Answering "who is actually paying today" means checking each venue live and reading what comes back. What you are buying is the negative results as much as the positive ones: knowing a venue is empty is the expensive half, and nobody publishes it. To pay, call the endpoint. It answers `402` with machine-readable terms in `accepts`. Sign a payment for those terms, retry with the `X-PAYMENT` header, and the body is served. Any x402 client handles this. Settlement runs through `https://facilitator.payai.network`, which sponsors gas. Terms are scheme `exact`, network `eip155:8453` (Base mainnet), asset `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` (USDC), amount `10000`, which is 0.01 USDC. What the data does and does not claim. Live task counts are re-polled on request, at most every 120 seconds. Venue verdicts are dated and baked in at deploy time; the payload reports how many days old they are and warns past a week, so treat them as dated claims rather than current state. A venue we could not reach reports `null`, never `0`, because unknown is not zero. If a live source is unreachable the endpoint returns `503` and does not charge, since we would rather serve nothing than sell a failed poll. Rewards are as published by each venue and are not a promise of payment. ## Endpoints - [Agent work index](https://opdevio.xyz/v1/agent-work): which task marketplaces have open funded work at this moment, and which are empty. Live task detail with rewards, deadlines and current submission counts, plus a venue table with dated verdicts on payment rails, KYC and stated agent policy. 0.01 USDC on Base, settled over x402. - [V1 X402](https://opdevio.xyz/v1/check/x402): Pre-flight an x402 resource before paying it: 402 shape, payment terms, HEAD and OPTIONS support, host-vs-advertised-resource mismatch, testnet detection, Bazaar declaration 0.01 USDC. - [V1 Agent Access](https://opdevio.xyz/v1/check/agent-access): Whether an agent can consume a site: robots.txt policy, llms.txt presence and conformance to the llmstxt.org structure, /.well-known/ard.json, HEAD support and CORS 0.01 USDC. - [V1 Tls](https://opdevio.xyz/v1/check/tls): TLS certificate health for a host: verification, days until expiry, issuer, whether a SAN actually covers the hostname, negotiated protocol 0.01 USDC. - [V1 Headers](https://opdevio.xyz/v1/check/headers): Response security headers for a URL: HSTS, CSP, nosniff, framing, referrer policy, and whether the server discloses its version 0.01 USDC. - [V1 Address](https://opdevio.xyz/v1/check/address): Sanity-check an EVM payment destination before funding it: shape, zero address, whether it is a contract, outbound transaction count, native and USDC balance, and whether it has ever been used on that chain 0.01 USDC. - [V1 Package](https://opdevio.xyz/v1/check/package): Look at an npm or PyPI package before installing it: does it exist, how many versions, when last published, does it declare install-time scripts, and is the name within two edits of a popular package 0.01 USDC. - [V1 X402 Seller](https://opdevio.xyz/v1/check/x402-seller): Why your x402 endpoint is not in the catalogue, and what to change. Returns the exact validator checks your resource fails, the fix for each, and how many other listed endpoints fail the same check. 52 percent of the catalogue fails at least one. 0.01 USDC. - [V1 Sec Facts](https://opdevio.xyz/v1/sec/facts): Reported financial figures for any SEC filer, by ticker or CIK, without reading the filing. Apple's XBRL company facts are 3.8 MB and about a million tokens across 505 tags; one answer is a few hundred. Every figure carries the period it covers, because XBRL publishes a quarterly and a year-to-date number sharing one end date and taking the newest row silently returns the wrong one. 0.02 USDC. - [V1 Spec Digest](https://opdevio.xyz/v1/spec/digest): Turn an OpenAPI or Swagger description into the handful of operations you actually need. Give it a spec URL and an optional query and it returns the matching operations with method, path, required parameters, auth schemes and response codes. GitHub's public description is 13 MB and about 3.2 million tokens across 1,239 operations; the answer to one question is a few hundred. 0.02 USDC. - [V1 Data X402 Conformance](https://opdevio.xyz/v1/data/x402-conformance): Which listed x402 endpoints pass the catalogue validator and which fail, for 10,811 endpoints checked 2026-09-18. 52.1 percent fail. Per endpoint: the verdict, the exact failing checks, protocol version and 30-day call and payer counts. Aggregates free; this returns the table. 2 USDC. - [V1 X402 Listed](https://opdevio.xyz/v1/check/x402-listed): Before you pay an x402 endpoint, ask whether it conforms. Looks one resource URL up in a catalogue-wide validator sweep and returns its verdict and the exact checks it failed. 0.01 USDC. - [V1 Data Bazaar Snapshot](https://opdevio.xyz/v1/data/bazaar-snapshot): Every x402 Bazaar listing with its own 30-day settled-payment counters, captured 2026-09-18: 15,616 entries with price, total calls, unique payers, last-called time, protocol version and whether the entry carries a bazaar schema. The aggregate view is free; this returns the per-entry table. 2 USDC. - [V1 Json Schema](https://opdevio.xyz/v1/check/json-schema): Validate a JSON document and check if it is a well-formed JSON Schema: valid JSON, top-level type, $schema declaration, legal type values, resolvable local $ref pointers, required as string arrays 0.01 USDC. - [V1 Redirect Chain](https://opdevio.xyz/v1/check/redirect-chain): Follow a redirect chain up to 10 hops: each hop's status and location, whether the scheme ever downgrades from https to http, whether it crosses to a different registrable domain, and whether the chain terminates or loops 0.01 USDC. - [Service catalogue](https://opdevio.xyz/v1/services): every paid route, its price and its free preview. No payment, no headers. - [Free previews](https://opdevio.xyz/v1/agent-work/preview): append `/preview` to any paid route. Previews return the verdict and counts without the detail, which is enough to decide whether the paid call is worth making. ## Optional - [Agent-readable service description](https://opdevio.xyz/.well-known/ard.json): the same terms as a machine-readable record. - [Source and published tools](https://github.com/opdevio): our public repositories. - [Contact](mailto:hello@opdevio.xyz): hello@opdevio.xyz.