myncellium paid api
docs

Everything an agent
needs to pay you back.

x402 (USDC on Solana). No API key, no signup. live: payments enforced (mainnet)

Quickstart

1 · Free discovery

curl https://paid.myncellium.com/openapi.json              # OpenAPI 3.1, x-payment-info per operation
curl https://paid.myncellium.com/.well-known/x402          # x402 discovery manifest
curl https://paid.myncellium.com/.well-known/agent-card.json  # A2A agent card
curl https://paid.myncellium.com/llms.txt                  # agent-readable summary

2 · Free trial (1 call per IP per day)

curl "https://paid.myncellium.com/x402/market/price?q=weather&trial=1"

3 · Paid call (x402)

curl -i https://paid.myncellium.com/x402/audit?url=https://example.com/.well-known/x402
#   -> HTTP 402, header payment-required: base64(x402 v2 accepts)
#   pay accepts[0] in USDC (Solana) with any x402 client/facilitator
curl -H "payment-signature: <signed x402 payment>" \
     "https://paid.myncellium.com/x402/audit?url=https://example.com/.well-known/x402"
#   -> 200 + payment-response header (transaction proof)

Any x402-compatible client works (standard x402 v2 challenge). Facilitator: facilitator.payai.network, buyer-side gas sponsored. MCP equivalents: paid_x402_market, paid_model_price, paid_x402_audit.

HTTP endpoints

EndpointPriceParamsReturns
GET /x402/market/price$0.005q, type, max_price_usd, limitCheapest matching x402 services + market price distribution.
GET /x402/model/price$0.003provider, model, tokens_in, tokens_outLLM prices with official sources + estimated call cost.
GET /x402/audit$0.01urlPre-payment readiness/trust check for any x402 URL.
POST /a2a$0.005JSON-RPC message/sendA2A task answered statelessly (see agent card).
POST /mcp—JSON-RPC tools/callAny exposed MCP tool; prices below.

MCP (JSON-RPC over HTTP)

GET /mcp is free discovery. Paid calls go to POST /mcp as JSON-RPC tools/call; unpaid returns 402 with payment-required, paid returns the tool result.

curl -i -X POST https://paid.myncellium.com/mcp -H "content-type: application/json" -d '{
  "jsonrpc": "2.0", "id": 1, "method": "tools/call",
  "params": { "name": "paid_answer", "arguments": { "question": "What is x402?" } }
}'

initialize and tools/list are always free. Batch requests bill the most expensive tool in the batch.

Native tools & prices

Prices per call in USD, settled in USDC on Solana. Full schemas in /openapi.json (x-tools).

ToolDescription
paid_answer
$0.005
Stateless answer API. Answers the buyer's question with a language model; NO local or server context is used. Returns only the answer text. Paid per call.
example args
{"question":"What is the x402 protocol?"}
paid_review_snippet
$0.008
Stateless code review. Sends ONLY the provided snippet to the model and returns findings (bugs, security, edge cases, fixes). No repository or local context is used. Paid per call.
example args
{"code":"function add(a,b){ return a - b }","language":"javascript"}
paid_extract
$0.008
Stateless structured extraction. Sends ONLY the provided text (and optional schema) and returns a JSON object. No local context is used. Paid per call.
example args
{"text":"Name: Ada, age: 36"}
paid_translate
$0.005
Stateless translation API. Translates ONLY the provided text into the target language. No local context is used. Paid per call.
example args
{"text":"Hello, world!","target":"Portuguese"}
paid_summarize
$0.008
Stateless summarization API. Summarizes ONLY the provided text. No local context is used. Paid per call.
example args
{"text":"Long article text ..."}
paid_cve_lookup
$0.002
CVE / vulnerability lookup via OSV.dev. Give a CVE id (e.g. CVE-2021-44228) or a package+version. Returns severity, summary, affected ranges and fixed versions. Read-only, no local context. Paid per call.
example args
{"cve":"CVE-2021-44228"}
paid_dns_intel
$0.004
DNS intelligence for a domain via DNS-over-HTTPS: A, AAAA, MX, TXT, NS and CNAME records. Read-only, no local context. Paid per call.
example args
{"domain":"example.com"}
paid_repo_health
$0.004
Public GitHub repository health check: stars, archived/maintenance status, license, last push, open issues/PRs, topics. Read-only, no local context. Paid per call.
example args
{"repo":"anomalyco/opencode"}
paid_hash
$0.0005
Deterministic hash of a text string (sha256 default; sha512, sha1, md5). Pure compute, no network. Paid per call.
example args
{"text":"abc","algo":"sha256"}
paid_convert
$0.001
Pure-compute data conversion (no network): json_pretty, json_minify, json_to_csv, csv_to_json, base64_encode, base64_decode. Paid per call.
example args
{"op":"json_to_csv","data":"[{\"a\":1}]"}
paid_crypto_price
$0.002
Live crypto token prices (USD or other vs_currency) for one or more coins via CoinGecko. Read-only, no local context. Paid per call.
example args
{"ids":"solana","vs_currency":"usd"}
paid_gtin_lookup
$0.003
EAN/UPC/GTIN barcode lookup via Open Food Facts: returns product name, brand, quantity and Nutri-Score when available. Read-only, no local context. Paid per call.
example args
{"gtin":"3017620422003"}
paid_config_review
$0.008
Stateless review of an infrastructure configuration (YAML, Docker Compose, Kubernetes, Terraform) provided by the caller: risks, hardening and concrete fixes. No repository or local context. Paid per call.
example args
{"config":"services:\n  db:\n    image: postgres\n    ports: ['5432:5432']","kind":"docker-compose"}
paid_x402_market
$0.005
x402 market intelligence: prices of OTHER agents/services across public x402 directories (facilitator Bazaar + x402scan). Optionally filter by keyword, resource type or max price and get the cheapest matching services with prices, plus the market price distribution. Public data only; no local context. Paid per call.
example args
{"query":"weather","type":"http","max_price_usd":0.05}
paid_model_price
$0.003
LLM price oracle with official sources: input/output USD per 1M tokens for a provider:model plus the estimated cost of a call. Sourced from a verified price table; if there is no official source the values are null (never invented). Paid per call.
example args
{"provider":"groq","model":"openai/gpt-oss-120b","tokens_in":1000,"tokens_out":500}
paid_llm_route
$0.004
LLM routing catalog: given an optional need keyword and a budget, returns provider:model options with sourced prices (USD per 1M tokens), free-tier flags and signup links, cheapest first. Public catalog data; no local context. Paid per call.
example args
{"need":"code","max_price_usd":1,"limit":5}
paid_x402_audit
$0.01
Pre-payment readiness/trust check for any x402 service URL: is it reachable, does it return a valid 402 challenge, what are its accepts (network/asset/amount/payTo), is the challenge signable (EIP-712 params), is an input schema present, and a verdict. Read-only probe of PUBLIC URLs only (SSRF-guarded). Paid per call.
example args
{"url":"https://example.com/x402/endpoint"}

A2A

Agent card (free): https://paid.myncellium.com/.well-known/agent-card.json. Paid task: POST /a2a with message/send and message.parts[].text; returns an A2A task with the stateless answer. x402 extension declared on the card.

Limits & guarantees

  • Stateless: paid tools use only your input — no local/server context. Telemetry is redacted (no arg content) and secret-free.
  • Rate limit: 60 req/min per IP · body up to 1 MB · request timeout 180 s.
  • Trial: 1 free call per IP per day on /x402/* via ?trial=1 (never affects directory probes or paid traffic).
  • Never invented: prices and market data come from public directories/official sources; missing data is null.
  • Chains: USDC on Solana (mainnet) · facilitator PayAI · buyer-side gas sponsored.

Contact

Questions, integrations or abuse reports: info.contact.email in /openapi.json, or the ERC-8004 registration.