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

Read-only probes

MCP server · Data access / search

US Codex

By uscodex.org Verified namespace

Federal law: US Code, CFR, public laws, bills and executive orders, cross-linked and versioned.

WebsiteDeveloper tools & code
Connect to US Codex
Checks passed
12 / 22

2 failed · 8 not measured

Median response
651 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?
310
Publisher identityCan the publisher be traced to its source?
312

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 651 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name uscodex.

  • Pass
    Lists tools

    tools/list returned 5 tools.

  • Pass
    Current protocol

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

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 651 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 651 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%.

  • Fail
    Safety hints

    5 tools set neither readOnlyHint nor destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-09-25T03:16:24.379564Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using US Codex

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 us-codex https://uscodex.org/mcp

Capabilities

Tools 5

citations

What cites a document: each corpus's citations of a code section, law, bill or order, with the words that cite it, and for a statute the regulations issued under it. Lists come 50 at a time; `list` and `offset` page through one.

Discovered
compare

What changed in a code section between two releases: each provision added, removed, changed or renumbered, the edits marked <del> and <ins>. To compare versions of a bill, take the 'what changed' link from its history.

Discovered
fetch

Read a document or page of the site as markdown: a code section with its notes, a title's or unit's contents, a public law, a bill (at any version), an executive order. Paths also reach the corpus indexes ("/usc", "/pl?congress=118", "/bills?congress=119", "/eo") and each code's releases ("/usc/releases"). Links in the markdown are paths this tool accepts.

Discovered
history

How a document came to be: for a code section, the laws that enacted and amended it and every release that changed its text; for a law or bill, its legislative history, each version linked to its text and to what changed from the one before.

Discovered
search

Search the full text of federal law: United States Code, Code of Federal Regulations, Public Laws, Congressional Bills, Executive Orders. Results are ranked across every corpus unless `corpus` narrows them, each with its citation, a link and the matching words. A query that is only a citation returns that document instead.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected651 ms5

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