PayAPI Market
REMOTE · PAYAPI.MARKET
Search settlement-verified x402 APIs for free. Pay providers in USDC on Base, Solana or Algorand.
Available components
Last scanned (2 hours ago)
Scores higher than 85% of remote servers
Reachable. Last reached 5 Nov 2026.
Category Crypto and Web3
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →
Endpoint Security80
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability55
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 1801 tokens (~450/item across 4 items; 4 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
- No destabilizing schema changes in the last 30 days.Pass
Tool Coverage97
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 90% of tool parameters carry a description.Partial
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 4 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities60
- Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28. See how to fix → Fail
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 1 Nov 26 −1
- The server rewrote its instructions, which are the text every model session reads security
- Tool “get_api” rewrote its description, which is the text the model reads security
- Tool “submit_listing” rewrote its description, which is the text the model reads security
- Schema quality: 351 → 450 ▼ functional
- “submit_listing” added an optional parameter “email” cosmetic
- “submit_listing” added an optional parameter “url” cosmetic
- “submit_listing” added an optional parameter “urls” cosmetic
- “submit_listing” reworded the description of “base_url” cosmetic
- “submit_listing” reworded the description of “category” cosmetic
- “submit_listing” reworded the description of “contact_email” cosmetic
- “submit_listing” reworded the description of “description” cosmetic
- “submit_listing” reworded the description of “method” cosmetic
- “submit_listing” reworded the description of “name” cosmetic
- “submit_listing” reworded the description of “networks” cosmetic
- “submit_listing” reworded the description of “paid_route_url” cosmetic
- “submit_listing” reworded the description of “payTo” cosmetic
- “submit_listing” reworded the description of “price” cosmetic
- “submit_listing” reworded the description of “sample_input” cosmetic
- “submit_listing” made “category” optional cosmetic
- “submit_listing” made “description” optional cosmetic
- “submit_listing” made “name” optional cosmetic
- “submit_listing” made “paid_route_url” optional cosmetic
- “submit_listing” made “payTo” optional cosmetic
- “submit_listing” made “price” optional cosmetic
- “submit_listing” made “sample_input” optional cosmetic
- 31 Oct 26 0
- A breaking change shipped without a version bump: still 1.1.0 ▼ security
- Tool “submit_listing” rewrote its description, which is the text the model reads security
- Schema quality: 305 → 351 ▼ functional
- “submit_listing” made “sample_input” required, so existing callers break ▼ functional
- “submit_listing” added an optional parameter “example_expected_output” cosmetic
- “submit_listing” added an optional parameter “input_param_to_vary” cosmetic
- “submit_listing” added an optional parameter “method” cosmetic
- “submit_listing” added an optional parameter “sample_url” cosmetic
- “submit_listing” added an optional parameter “settles_after_success” cosmetic
- “submit_listing” reworded the description of “sample_input” cosmetic
- 28 Oct 26 0
- The server rewrote its instructions, which are the text every model session reads security
- Tool “submit_listing” rewrote its description, which is the text the model reads security
- 21 Oct 26 0
- The server rewrote its instructions, which are the text every model session reads security
- Schema quality: 233 → 290 ▼ functional
- Tool coverage: 67% → 86% ▲ functional
- Server version: 1.0.0 → 1.1.0 functional
- New tool “submit_listing” functional
- 20 Oct 26 0
- “list_apis” reworded the description of “network” cosmetic
- “search_apis” reworded the description of “network” cosmetic
2 cosmetic changes on this day. Switch on “Show cosmetic changes” to see them.
- 13 Oct 26 0
- Schema quality: 201 → 230 ▼ functional
- Tool coverage: 57% → 67% ▲ functional
- “list_apis” added an optional parameter “network” cosmetic
- “search_apis” added an optional parameter “network” cosmetic
- 12 Oct 26 −1
- The server rewrote its instructions, which are the text every model session reads security
- Tool “get_api” rewrote its description, which is the text the model reads security
- 10 Oct 26 +7
- Authorization: unverified → partial ▲ security
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 5 Nov 2026 · Probed https://payapi.market/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=payapi.market | CN=YR2,O=Let's Encrypt,C=US | 12 Oct 2026 | 10 Jan 2027 | RSA 2048 | SHA256-RSA | 6ea2eb0918ed257b47a4aecade4cc8dc6b7 |
| SANs: payapi.market | ||||||
| CN=YR2,O=Let's Encrypt,C=US (CA) | CN=Root YR,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | RSA 2048 | SHA256-RSA | 4ebd24947e24d394802d84a52fd5b319 |
| CN=Root YR,O=ISRG,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | RSA 4096 | SHA256-RSA | f24b6d17f9d9ad7cb1c9fea78782699f |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of payapi.market. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| market. | present | 40531, 62735 | 8, 8 | Verified |
| payapi.market. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000; includeSubDomains; preload |
| content-security-policy | default-src 'self'; script-src 'self' 'unsafe-inline' https://cloud.umami.is https://js.stripe.com; style-src 'self' 'unsafe-inline' https://fonts.googleapis.com; font-src 'self' data: https://fonts.gstatic.com; img-src 'self' data: blob: https:; connect-src 'self' https://*.supabase.co wss://*.supabase.co https://api.stripe.com https://cloud.umami.is https://gateway.umami.is https://*.payapi.market https://api.airtable.com; frame-src https://js.stripe.com https://hooks.stripe.com https://checkout.stripe.com; object-src 'none'; base-uri 'self'; form-action 'self'; upgrade-insecure-requests |
| x-content-type-options | nosniff |
| x-frame-options | DENY |
| referrer-policy | strict-origin-when-cross-origin |
| permissions-policy | camera=(), microphone=(), geolocation=(), payment=(self "https://js.stripe.com"), interest-cohort=() |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://payapi.market/mcp | Verified | 200 | |
| http (plaintext) | http://payapi.market/mcp | HTTPS enforced | 308 | https://payapi.market/mcp |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
get_api Get one PayAPI Market listing ~237
Fetch a single live listing by its id or slug, including base_url, price range, network and verification state. payment_verified is true if at least one route was paid; verified_routes names each paid route with its on-chain receipt. test_payment_usdc is the test payment, not the per-call price. amount_usdc is deprecated and has the same value; it is the verification test payment, not the price. The per-call price is price_min and price_max. Also returns a reliability object: score (0 to 100 or null), band (strong, established, thin, caution or unscored) and computed_at. Reliability is a running score from paid verifications, health history and payTo integrity, not a star rating and not a guarantee; unscored means it has not been computed for that listing yet. Method: https://payapi.market/how-an-agent-finds-payapi. Returns the listing whether or not it is verified, and reports payment_verified honestly. Free and read-only; spends nothing.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | Listing uuid or slug, as returned by search_apis or list_apis. |
No output schema declared.
No examples provided.
list_apis List the PayAPI Market catalogue ~130
Browse the live catalogue, optionally filtered to one category. Omit category for everything. Returns settlement-verified listings only unless verified_only is false. Free and read-only; spends nothing.
| Name | Type | Req | Description |
|---|---|---|---|
| category | string | – | Exact category name. Call with no category first to see the valid values. |
| limit | integer | – | – |
| network | string | – | Only listings that accept USDC on this network: base, solana, algorand, or a CAIP-2 id. Omit for all. Each listing reports its rails in `networks`. |
| verified_only | boolean | – | – |
No output schema declared.
No examples provided.
search_apis Search the PayAPI Market catalogue ~146
Free-text search across the live catalogue. Matches listing name, description, category and provider name. Returns settlement-verified listings only unless verified_only is false. Free and read-only; spends nothing.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | – |
| network | string | – | Only listings that accept USDC on this network: base, solana, algorand, or a CAIP-2 id. Omit for all. Each listing reports its rails in `networks`. |
| query | string | yes | What you are looking for, e.g. "uk property" or "sanctions screening". |
| verified_only | boolean | – | Restrict to settlement-verified listings. Default true. |
No output schema declared.
No examples provided.
submit_listing Submit a listing to PayAPI Market ~804
List one or more APIs. The minimum is a paid URL (url, paid_route_url, or urls) and contact_email (email is accepted as the same field). Price, payTo, network, description and name are read from the HTTP 402 when you omit them. Category defaults to Data, which the listing schema accepts. urls takes at most 20 routes. Each route is probed and returned in results as listed, pending or rejected, with a code and a hint when it is turned away. A no-input GET that returns a valid 402 may omit sample_input. Placeholder examples are rejected. NEVER sets payment_verified or makes the listing live. PayAPI Market may test it with a real paid call (up to $0.10 USDC on Base). Listing is free. Providers keep 100%. Rate limited: max 10 submissions per hour per wallet and per contact email, 50 per day per IP and per payTo address. The cap still applies inside a urls array. If this wallet already submitted this API, the result is the existing listing id and the message "This API has already been submitted." No second row is created. The same wallet and email can update a listing that is still pending review.
| Name | Type | Req | Description |
|---|---|---|---|
| base_url | string | – | Base URL of the API (https only, no localhost or tunnels). Defaults to the paid route origin. |
| category | string | – | API category. Defaults to Data when omitted. There is no Other category. |
| contact_email | string | yes | Contact email for the provider. Required. email is the same field. |
| description | string | – | API description. Read from the 402 or /.well-known/x402 when omitted. |
| string | – | Same as contact_email. | |
| example_expected_output | string | – | Optional JSON shape or short sample the free check compares against. |
| input_param_to_vary | string | – | Optional parameter name to change between two free sample calls, for example city. |
| mcp_endpoint | string | – | Optional: MCP endpoint URL if this is an MCP server |
| method | string | – | How we call the paid route. Read from the 402 when omitted. GET uses sample_input as a query string. POST uses it as a JSON body. |
| name | string | – | API name. Read from the 402 when omitted. |
| network | string | – | Only listings that accept USDC on this network: base, solana, algorand, or a CAIP-2 id. Omit for all. Each listing reports its rails in `networks`. |
| networks | array | – | Networks this API accepts (e.g. ["base"], ["base", "solana"]). The Base rail is read from the 402. |
| paid_route_url | string | – | The exact route that requires x402 payment. Same as url. |
| payTo | string | – | Base wallet that receives USDC. Read from the 402 when omitted. |
| price | number | – | Price per request in USDC. Read from the Base accept when omitted. |
| provider_name | string | – | Optional: provider/company name (defaults to API name) |
| sample_input | string | – | Example request. A query string for GET (city=London) or a JSON body for POST ({"city":"London"}). Read from the 402 when omitted. A no-input GET with a valid 402 may leave this empty. Placeholders a… |
| sample_url | string | – | Optional free sample or health URL. Called unpaid, before any paid check. |
| settles_after_success | boolean | – | Confirm the paid route settles only after a successful response. Required only when the server switch is on. |
| url | string | – | One https route that returns HTTP 402. Use this, paid_route_url, or urls. |
| urls | array | – | Up to 20 paid routes in one call. Each is probed on its own. |
No output schema declared.
No examples provided.
How do I install the PayAPI Market MCP server?
PayAPI Market is a hosted endpoint at https://payapi.market/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
remote · payapi.market
claude mcp add --transport http market-payapi-marketplace 'https://payapi.market/mcp'
What is the PayAPI Market MCP server?
PayAPI Market is an MCP server listed in the public MCP registry as market.payapi/marketplace. Search settlement-verified x402 APIs for free. Pay providers in USDC on Base, Solana or Algorand. This page covers its hosted endpoint (https://payapi.market/mcp).
Is the PayAPI Market MCP server safe to use?
PayAPI Market scores 82 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the PayAPI Market MCP server expose?
PayAPI Market exposes 4 tools: search_apis, list_apis, get_api, submit_listing. Their descriptions and schemas cost roughly 1,317 tokens of context every time the server is loaded.
Does the PayAPI Market MCP server require authentication?
No. We connected to PayAPI Market without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the PayAPI Market MCP server still maintained?
PayAPI Market is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.