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Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Data access / search

io.github.cyanheads/first-epss-mcp-server

Look up FIRST EPSS scores and daily history, find CVEs by threshold, and prioritize them with CVSS.

Checks passed
14 / 22

0 failed · 8 not measured

Median response
1057 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
5

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 1057 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name first-epss-mcp-server.

  • Pass
    Lists tools

    tools/list returned 5 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 1057 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 1057 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    21 of 21 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Pass
    Repo owner matches

    The GitHub repository owner matches the namespace login.

  • Pass
    Recently updated

    Updated 2026-10-29T02:54:13.471982Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using io.github.cyanheads/first-epss-mcp-server

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http io-github-cyanheads-first-epss-mcp-server https://first-epss.caseyjhand.com/mcp

Capabilities

Tools 5

epss_get_scores

Retrieve latest available or historically dated FIRST EPSS probability and percentile for supplied CVEs. Process up to 500 unique entries from batchOffset; response byte limits can return fewer whole entries. Resume with nextBatchOffset as batchOffset, the original cves and returned score date as date. deferredCves were not queried; withheldCves were processed but omitted, and either list can be a declared preview. Missing scores remain unknown; use epss_list_reference for coverage and interpretation.

Discovered
epss_get_timeseries

Retrieve an EPSS anchor and up to 30 preceding daily observations for up to 50 unique CVEs from batchOffset. Response byte limits retain whole history items. Resume CVE batches with nextBatchOffset as batchOffset, the original cves and returned score date as date; withheldCves were processed, deferredCves were not queried, and lists can be declared previews. Exact 7-day and 30-day deltas require their calendar baselines; gaps remain unknown. Model boundaries do not explain score movement. Re-anchor using previousAnchorDate for the preceding history window; that snapshot may be unavailable.

Discovered
epss_list_reference

Explain FIRST EPSS interpretation, model publishing dates, lookup coverage and transparent prioritization policy. Use this static reference before interpreting missing scores, score movement or probability versus percentile thresholds.

Discovered
epss_prioritize_cves

Assign remediation tiers using latest or dated EPSS and caller-supplied CVSS base severity. Defaults are severity >= 7 and EPSS probability >= 0.10; select percentile explicitly for population rank. Missing severity stays in epssOnly and missing EPSS stays unscored. Thresholds are policy conventions, not FIRST guidance. Process up to 500 unique entries from batchOffset, returning whole entries within the byte budget. Resume using nextBatchOffset as batchOffset, the original cves with original cvssBaseScore values, returned score date as date, and the same severityThreshold and likelihood. Deferred lists may be declared previews; withheldCves were already processed.

Discovered
epss_query_threshold

Discover CVEs using inclusive EPSS or percentile bounds, CVE year or dataset-addition recency; filters intersect and at least one is required. Examine one candidate page in the upstream FIRST order, which is not ranked by EPSS, so the first page does not hold the highest scores. Each serialized response surface fits 65536 UTF-8 bytes; budgetLimited and withheldCount disclose whole matches withheld, with nextOffset at the first withheld match. Year filtering can return an empty page with nextOffset; candidateTotal is a broad-query total, not an exact-year total. Continue with the same filters, limit, returned score date and nextOffset.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected1057 ms5