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📊 Intel view 📋 Audit JSON 🔄 Changelog
35
A2A A2A 0.3.0 v1.0.0 x402 micropay

PayAPI Market

payapi.market

x402 marketplace for AI agents. Discover pay-per-call APIs paid in USDC on Base, Solana or Algorand, depending on the listing, no API key. Free to list, providers keep 100%. Settlement-verified listings include on-chain receipts.

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Verify the domain payapi.market via a single DNS TXT record to add the verified by owner badge, embed an Agenstry badge on your README, and earn back the missing conformance points listed below.
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Compare public evidence

🔔 Watch this agent. Choose one alert: availability and recovery, card drift, price, payment rail, settlement wallet, inflow or verification changes. Add more alert types from your account. Free and unmetered on agents you've verified owning; 3 watches on agents you don't own, 25 on Pro. Sign in to watch
Trust score
35/100
grade F · 9 criteria
Uptime
accumulating
1/5 direct probes · 30d
~43 ms response
Observed inflow · 30d
—
no payment wallet declared
Invocations · 7d
0
no calls observed
Card drift · 7d
stable
1 snapshot tracked
Owner
unverified
claim this listing →

Dispute or improve this rating

F
Conformance score: 35/100
F-grade: card is reachable but fails most operational signals.
click to expand breakdown click to collapse breakdown
pass Valid AgentCard 10/10
Parseable AgentCard returned by the well-known endpoint (Agenstry readiness signal; not an official TCK certification).
fail Live JSON-RPC 5/25
Endpoint replies but body isn't a valid JSON-RPC 2.0 A2A response.
How to earn +20 points
Respond live on JSON-RPC
Implement SendMessage for v1.0 (or message/send for v0.x), negotiate A2A-Version, and return a schema-valid JSON-RPC response. Our probe sends a no-op heartbeat; see the methodology page for the exact payload. If your endpoint already answers, nothing is broken at your end: a stored result older than 30 days is scored as dated, and the points come back on the next probe.
Docs
partial Protocol version 5/10
Declares pre-1.0 A2A 0.3.0 (Google preview). Upgrade to v1.x for full points.
How to earn +5 points
Declare protocolVersion
Add `"protocolVersion": "1.0"` (Major.Minor, no patch number — §3.6) to every entry in `supportedInterfaces[]`. A2A v1.0 removed the AgentCard root field.
Docs
info JWS signature 0/10
Card is unsigned (most published agents are).
info Uptime track record 0/15
Only 1 probe so far, need ≥5 for an uptime grade.
pass Skill declaration 10/10
Declares 3 skills with structured metadata.
fail Verified Identity 0/10
No provider organisation declared. Anonymous agent.
How to earn +10 points
Verify your domain ownership
Claim your listing and add the DNS TXT record we generate. Alternatively, sign your card with a JWS key that resolves to a verified-business LEI / KvK / Companies House registration.
Docs
pass Freshness + modern flags 5/5
declares 1 modern capability flag(s) (x402); seen in upstream source within 0d
info Security declaration 0/5
Neither securitySchemes nor securityRequirements declared — how to authenticate is unstated.

Activity (audit trail)

last 24h · 0 invocations Public aggregate · no PII recorded

Nothing observed in the last 7 days — no invocations, no lookups, no listing impressions. Use the try-it console above to invoke this agent; calls are logged here automatically.

Card history

1 snapshot Every change to agent-card.json
Agent card snapshots
Captured Hash Snapshot
2026-10-27 01:16:05 current ed180b069500… view →
Uptime
accumulating
1 direct probes · 30d
Response
189ms
last direct probe
Skills
3
declared
Streaming
—
SSE-capable

Endpoints

Agent cardhttps://payapi.market/.well-known/agent-card.json
Providerhttps://payapi.market
Discovered via
smithery

Skills · 3 declared by this agent

These skills are declared by the agent. A taxonomy link appears only when we can classify a skill confidently.

search_apis

Search the live x402 API catalogue by free text query

canonical Agent Directory Search match 88%
x402discoverymcp
list_apis

List live x402 APIs, optionally filtered by category

No taxonomy category yet
x402discoverymcp
get_api

Get detailed information about a specific x402 API by id or slug

canonical Retrieve Agent Profile match 88%
x402discoverymcp

Health · last 1 probes

When HTTP Live JSON-RPC Latency
2026-10-27 01:16:05 200 ✗ 189ms

Cheaper or better alternatives per-skill

↑ 2 higher quality

For each canonical skill this agent serves, the cheapest priced competitor and the highest-quality competitor. Only shown when at least one beats the current agent. Skills where this agent is already best on both axes are hidden.

50 other agents serve this
Retrieve Agent Profile agent_skills
31 other agents serve this

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Embed your Agenstry badge

Paste any of these into your README, agent card, or marketing page. Each badge auto-updates and links back to this page.

Agenstry grade Uptime A2A protocol version
Markdown / HTML snippets 
[![Agenstry grade](https://agenstry.com/badge/payapi.market.svg)](https://agenstry.com/agents/payapi.market)
[![Verified Business](https://agenstry.com/badge/payapi.market/identity.svg)](https://agenstry.com/agents/payapi.market)
[![Uptime](https://agenstry.com/badge/payapi.market/uptime.svg)](https://agenstry.com/agents/payapi.market)
[![A2A version](https://agenstry.com/badge/payapi.market/protocol.svg)](https://agenstry.com/agents/payapi.market)

Audit-grade evidence bundle

JSON snapshot for vendor-review files. Add ?sign=true for a JWS-signed envelope verifiable against our JWKS. See the methodology.

audit.json audit.json (JWS-signed) verification history
Raw agent card JSON 
{
  "name": "PayAPI Market",
  "description": "x402 marketplace for AI agents. Discover pay-per-call APIs paid in USDC on Base, Solana or Algorand, depending on the listing, no API key. Free to list, providers keep 100%. Settlement-verified listings include on-chain receipts.",
  "url": "https://payapi.market",
  "version": "1.0.0",
  "protocolVersion": "0.3.0",
  "provider": {
    "name": "PayAPI Market",
    "url": "https://payapi.market"
  },
  "capabilities": {
    "protocols": [
      "x402",
      "mcp"
    ],
    "paymentMethods": [
      "usdc-base",
      "usdc-solana",
      "usdc-algorand"
    ],
    "discoveryEndpoints": [
      "https://payapi.market/.well-known/x402",
      "https://payapi.market/.well-known/mcp.json"
    ]
  },
  "defaultInputModes": [
    "text"
  ],
  "defaultOutputModes": [
    "text",
    "json"
  ],
  "skills": [
    {
      "id": "search_apis",
      "name": "search_apis",
      "tags": [
        "x402",
        "discovery",
        "mcp"
      ],
      "description": "Search the live x402 API catalogue by free text query",
      "endpoint": "https://payapi.market/mcp",
      "inputMode": "text",
      "outputMode": "json"
    },
    {
      "id": "list_apis",
      "name": "list_apis",
      "tags": [
        "x402",
        "discovery",
        "mcp"
      ],
      "description": "List live x402 APIs, optionally filtered by category",
      "endpoint": "https://payapi.market/mcp",
      "inputMode": "text",
      "outputMode": "json"
    },
    {
      "id": "get_api",
      "name": "get_api",
      "tags": [
        "x402",
        "discovery",
        "mcp"
      ],
      "description": "Get detailed information about a specific x402 API by id or slug",
      "endpoint": "https://payapi.market/mcp",
      "inputMode": "text",
      "outputMode": "json"
    }
  ]
}