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paidfor

NPM · @PAIDFOR/MCP · 2 COMPONENTS

Check an x402 seller before paying: verdict, failure rate and evidence from paid calls on Base.

61 Trust /100

Last scanned (11 hours ago)

Scores higher than 31% of npm servers

Category Finance and Payments

Trust breakdown (7 categories)

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →

Supply Chain Security90
  • No malware found by supply-chain analysis.Pass
  • CVE check failed: a known high-severity CVE affects zod 3.25.76, reached via @paidfor/x402-safe-fetch > @x402/core > zod. A fixed version is available. View diagnostics → Fail
  • No install/post-install scripts declared.Pass
  • 31 of 113 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency19
  • Repository check failed: the declared repository URL returned HTTP 404. See how to fix → View diagnostics → Fail
  • Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
  • Clear OSI-approved license (MIT).Pass
  • Actively maintained (last published 6 days ago).Pass
  • Security-disclosure policy not yet verified: we couldn't inspect the source repository.Unverified
Schema Quality & AI Usability66
  • AI-judged instruction clarity (excellent).Pass
  • Context-footprint check failed: tool/resource definitions use about 1005 tokens (~251/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 Management0
  • Stability not yet verified: not enough scan history yet (needs a 30-day window).Unverified
Tool Coverage100
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 100% of tool parameters carry a description.Pass
  • Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
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
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass

Unverified: 1 category

A category scored 0 because we could not verify it: a data source with nothing on this package, evidence we could not reach, or a check we could not run. We only credit what we can confirm.

What we tested

Checks we ran (14)

  • Malware scan
  • Known CVEs
  • Install scripts
  • Dependency health
  • Source repository
  • Provenance
  • License
  • Maintenance
  • Schema quality
  • Tool coverage
  • Injection markers
  • Destructive annotations
  • Judged manipulation
  • MCP protocol

Checks we could not complete (2)

These are gaps on our side, not findings about this package. We only credit what we can confirm, so a category made up entirely of them scores 0.

  • Security disclosure in Provenance & TransparencySecurity-disclosure policy not yet verified: we couldn't inspect the source repository.
  • Stability in Stability & Change Management (scores 0 for this)Stability not yet verified: not enough scan history yet (needs a 30-day window).

Does not apply to this package (2)

  • Endpoint SecurityScored on hosted endpoints only. A package has no live endpoint of its own for us to probe.
  • Transport & ReachabilityScored on hosted endpoints only. A package has no live endpoint of its own for us to probe.

The score does not measure everything. What the score does not measure →

Changelog

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.

  • 30 Oct 26 61

    First indexed and scored.

Diagnostics

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 · Analysed npm/@paidfor/mcp@0.4.0

Provenance No attestation

The registry publishes no build provenance for this version, so there is nothing to verify.

Result No attestation
Ecosystem npm

Background: How many MCP packages publish verified provenance →

Vulnerabilities 1 finding
ID CVE Severity Vector Fix available
GHSA-mrhx-c7xc-m3w5 CVE-2023-54404 high CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H yes

Background: What a vulnerability scan can and cannot prove →

Dependencies 113 packages
Packages resolved 113
Stale 30
No linked repository 1
Tree resolution Complete

Background: SBOMs and build attestations, explained →

MCP tools · 4 exposed · ~669 tokens

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 →

Tool Tokens
check_x402_seller ~136

Call this before any x402 payment, before retrying a request that answered HTTP 402, or whenever the user is about to buy an API call with USDC on Base or names an API they intend to pay per call. Returns a verdict (avoid, caution, ok, unknown), one sentence to act on, the seller's paid-call count and failure rate with a 95% interval, listed price, modal quote and max overcharge ratio when known, and links to the seller page and raw evidence.

NameTypeReqDescription
urlstringyesx402 resource URL, or a bare seller domain such as api.example.com
NameTypeReqDescription
candidate–yesQueue state for a seller not yet measured; null otherwise
evidence_urlstring|nullyes–
generated_atstringyesWhen the index was generated
hoststring|nullyes–
methodology_urlstringyes–
probe–yesHourly unpaid probes of the seller's 402 quote; null when not probed
resource–yesMeasured paid calls to this exact URL; null when not measured
seller–yesMeasured paid calls to this seller; null when the study never paid it
seller_urlstring|nullyes–
verdictstringyes–
verdict_textstringyesOne sentence to act on, with the evidence link

No examples provided.

list_reliable_sellers ~145

Call this when choosing among sellers for a task, or when the user asks for a safe or reliable API. Returns sellers with zero failures across at least 30 paid calls, most-called first. For each: domain, category, paid-call count, the 95% upper bound on its failure rate, median quoted price in USDC, USDC paid to it in the last 30 days, when it was last seen, and its paidfor seller page.

NameTypeReqDescription
categorystring–Kind of service to list sellers for; omit to list every kind
limitinteger–How many sellers to return, most-called first; 50 when omitted
NameTypeReqDescription
generated_atstringyesWhen the index was generated
sellersarrayyes–

No examples provided.

recent_changes ~167

Call this when the user asks what changed, or before relying on a verdict older than a day. Returns recent changes, newest first: verdict changes, new failures by type, moved quotes, changed pay-to addresses, sellers added or reaching 30 paid calls, published seller replies, the operator-reported series maturing or disagreeing with ours. Each change has its time, type, seller domain, seller page and type-specific details (for example the old and new quote).

NameTypeReqDescription
hoststring–Seller to show changes for, as a bare domain such as api.example.com; omit for every seller
sincestring–Show only changes after this time, in ISO 8601 (such as the generated_at of a verdict you already have); omit for the latest changes
NameTypeReqDescription
countnumberyesMatching changes the index returned (it caps the feed at the newest 500); events holds at most the newest 100
eventsarrayyes–

No examples provided.

report_x402_payment ~221

After your agent pays an x402 seller with any wallet, report what came back. Needs the resource URL, the settlement transaction hash and the outcome. Free, no account, no key; the report counts only with on-chain proof.

NameTypeReqDescription
http_statusinteger–The HTTP status of the paid response, if known
outcomestringyesWhat came back: ok (the response was usable for its purpose), non_delivery (an error, an empty body or nothing usable after paying), wrong_goods (a usable response, but not what was asked for), overc…
quoted_usdc––The price the 402 quoted, in USDC, if known
tx_hashstringyesThe settlement transaction hash on Base: the `transaction` field of the seller's PAYMENT-RESPONSE or X-PAYMENT-RESPONSE header (base64 JSON)
urlstringyesThe x402 resource URL that was paid for
NameTypeReqDescription
amount_usdcstring|nullyesUSDC moved, read from the transaction
pay_tostring|nullyes–
payerstring|nullyesThe paying wallet, read from the transaction (never from the report)
reasonstring|nullyesWhy a report was rejected; null otherwise
sentencestringyesThe result in one sentence
statusstringyesverified: counted once folded in (minutes); pending: checked on Base again within minutes; duplicate: this transaction was already reported; rejected: not counted, see reason
verification_urlstring|nullyes–

No examples provided.

Install

How do I install the paidfor MCP server?

paidfor runs locally as an npm package, launched with npx -y @paidfor/mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

npm · @paidfor/mcp

# add to Claude Code
claude mcp add dev-paidfor-paidfor -- npx -y @paidfor/mcp
Common questions

What is the paidfor MCP server?

paidfor is an MCP server listed in the public MCP registry as dev.paidfor/paidfor. Check an x402 seller before paying: verdict, failure rate and evidence from paid calls on Base. This page covers its npm package (@paidfor/mcp).

Is the paidfor MCP server safe to use?

paidfor scores 61 out of 100 on VerifyMCP. We recorded 1 known advisory against it as of 5 November 2026. It declares no install or post-install scripts. 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 paidfor MCP server expose?

paidfor exposes 4 tools: check_x402_seller, list_reliable_sellers, recent_changes, report_x402_payment. Their descriptions and schemas cost roughly 669 tokens of context every time the server is loaded.

Is the paidfor MCP server still maintained?

paidfor 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.

What licence is the paidfor MCP server under?

paidfor declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

What did VerifyMCP test on the paidfor MCP server?

VerifyMCP ran 14 checks on paidfor, covering Malware scan, Known CVEs, Install scripts, Dependency health and 10 more. 2 items could not be completed, a gap on our side rather than a finding about paidfor: Security disclosure and Stability. One category scores 0 for that reason, because we only credit what we can confirm. Endpoint Security and Transport & Reachability do not apply to an npm package, so they were not tested. The score does not measure everything, and the scoring documentation lists what it leaves out.