Robin Saige we check the tools AI agents call

mercury x402 mcp

io.github.mercuryx402/mercury-x402-mcp

Agent-payable web data over x402: 18 keyless services an agent pays per call.

— the operator's own registry description reported

Publisher io.github.mercuryx402 · first seen 2026-08-12 · endpoint https://network.mercury-hq.com/mcp

allow
verdict
mid-slow-solo
cluster
ok_tools
answers
18
tools served

Dependency rating derived

allow
allow — alive & usable · kind unknown · V n/a
allow — because answers ●, 18 tools legible (band A) ●, no confirmed drift in 3 probes ●; not yet checked: truth (0 runs)

Cluster mid-slow-solo · distinctiveness 0.329 (typical). Every figure is a percentile or class within the 11,363-server censussee the whole spectrum.

Does it answer? Q1 · observed
answersalive_tools
latency495 ms
vs populationslow
protocolcurrent
authopen
Can it be used? Q4 · observed
tools18
vs populationmid
capabilities1
harnessA
Did it hold when checked? Q3–Q4 · derived
identitysolo
servers on its host1
verifiabilityunassessed
duplicate inventoryno
drift events0
answers trueno primary

🔏 Signed receipt rr_ca9f7f97eb0ac654c6e1750c · ed25519 · key rs-rcpt-2026-08 — this rating is tamper-evident; an agent gets the full signature from check_server and can verify it against the published key.

Q1Does it answer?alive & usable — 3 probes ●evidence ↓
Q2What is it?kind unknown ● evidence ↓
Q3Can it be checked?V n/a for this kind ◐evidence ↓
Q4Did it hold?harness A · truth not yet run · no drift ●evidence ↓
Q5What company does it keep?mid-slow-solo · 1 on its host (context, not verdict) ◐evidence ↓

● observed · ◐ derived · ○ reported — the verdict synthesizes Q1–Q4; Q5 is context. Methodology →

History observed

Every probe we made, oldest → newest (3 shown, 2026-08-12 → 2026-08-16). Green answered · amber answered-but-walled · red no useful answer. A gap in our cadence is a gap in coverage, not evidence about the server.

changelog (3 events)
datetypewhat changed
2026-08-16outcomeok_tools (was timeout)
2026-08-14outcometimeout (was ok_tools)
2026-08-12outcomefirst probe: ok_tools

What kind of tools these are derived

Verification only means something relative to a tool's NATURE — an email-sender has no "true answer", a generator has no answer key. Classification evidence: classified from tool names/descriptions/annotations WE OBSERVED. What checking applies to each kind (the full methodology →):

naturetoolsmeaning what checking applies
unclassified11not classifiable from its textTier-1 only until its tools describe themselves
action3changes the worldno true answer exists; we check the CONTRACT (destructive/read-only/idempotent declarations, error legibility) and never fire real actions
retrieval-public3serves public factstruth-checkable against a public source — the V-ladder applies in full
computational1deterministic transformsself-checkable by re-computation and known-answer tests

Tools last seen observed

availability batch diff dns extract feed fetch headers links markdown metadata notarize readability redirect robots sitemap table validate

Harness readiness observed

Can an agent's harness pick this tool and call it correctly? Graded on the three things an agent reads — name, description, typed parameters. Band A — an agent can pick and call these reliably.

legibility checktools passingok
name is clear & specific18/18
has a description18/18
description is substantive18/18
parameters are typed18/18
parameters are described18/18

18 of 18 tools graded · 18 with a captured input schema. RS-008, Tier-1 — no domain knowledge, applies to any tool. “Alive” is not the same as “usable”.

Truth checks observed

Not in the Tier-2 trade lane, or not yet checked. Tier-2 re-derives a server's answers against published primary sources — see truth checks.

Protocol conformance observed

2025-06-18
protocol version
session model
1.0.0
server version mercury-x402

Capabilities: tools

Drift observed

No confirmed drift on record. Baseline set 2026-08-16; changes appear here after human review.

raw probe records
probed (UTC) outcomehttpmsprotocol
2026-08-16T06:13:28Zok_tools2004952025-06-18
2026-08-14T19:59:51Ztimeout12060
2026-08-12T05:35:08Zok_tools2002532025-06-18

Watch or embed this verdict

verdict badge

Operators: put the live verdict in your README — it updates with every census, links back here, and is a dated observation, never a warranty:

[![Robin Saige verdict](https://robinsaige.com/badge/io.github.mercuryx402/mercury-x402-mcp.svg)](https://robinsaige.com/s/io.github.mercuryx402/mercury-x402-mcp)

Depend on it? Subscribe to its change feed — outcome changes and confirmed drift, no account needed. Building on it? The full dossier as JSON — verdict, rating, truth checks, history — stable enough to gate CI on.

← overview

Operator of this server? Everything we hold about it is on this page — free, no account, for anyone. Wrong attribution, stale probe, misclassification? Dispute this record →