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Evidence for your next connection.

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

Read-only probes

MCP server · Other

CompanyGraph

CompanyGraph: Written once, read by both

Checks passed
11 / 22

3 failed · 8 not measured

Median response
340 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
14

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?
222

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 340 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name companygraph-mcp-server.

  • Pass
    Lists tools

    tools/list returned 14 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 340 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 340 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.

  • Fail
    Parameters documented

    25 of 38 parameters have a description (66%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match 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 2026-09-21T11:34:18.387151Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using CompanyGraph

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 companygraph https://mcp.companygraph.io/mcp

Capabilities

Tools 14

describe_errors

What a refused call looks like. A tool's output schema covers its answers only, so use this once, to branch on refusals or validate them. No input. Returns `errors`, every `code` with `when` it is raised and the JSON Schema of its `details`, and `schema`, the JSON Schema of a whole refusal: `error` with `code`, `message`, `rule`, `details`, beside `model`.

Discovered
describe_relations

What the schemas declare between types: references with form and cardinality, ownership, enums, joins, list kinds. Use for a diagram or audit; for one type's full schema use describe_schema. Optional `type` narrows every list, `direction` (declares, declared-to, both; needs `type`) one side of relations, `via` relations and enums. Returns those lists, with `forms` and `reading` explaining every term. Not paged.

Discovered
describe_rule

One convention of the vocabulary as written, not a company's own rule (an entity of type `rule`: list_entities, get_entity). Input: `rule`, a number from list_rules such as R9, in either case. Returns `rule`, `title`, `part`, `text` and the file's `url`. An unknown number is refused with the known ones listed.

Discovered
describe_schema

One type's schema: its sections as written and its declared relations as data. Use to learn what an entity of the type may hold; for the whole vocabulary use describe_relations. Input: `type`. Returns `url`, the schema's own file, `sections`, and `relations`: owner, owns, references both ways, enums, joins and lists.

Discovered
diagram

A picture of the model as Mermaid; edge data: list_references. Input: `shape`; `id`, `domain`, `type` or `unit` narrow it. aggregate, flow, lifecycle take a context's `id`; organization without `id` draws the company; system a landscape, holds its data; usecase, scenario a use case's; requirements a feature's, product's, use case's or requirement's. Returns `mermaid`, `nodes`, `links`, `units`, counts. Max 50 nodes.

Discovered
fetch

One entity's page as written. Use to quote or display the source; for structured fields and references use get_entity. Input: `id` or address, from search, list_entities or any reference. Returns `id`, `title`, `type`, `url` and `text`, the Markdown source. Takes no name: search with match "name" finds the id.

Discovered
find_evidence

Every edge into one skill, grouped by the type of the page that drew it. Use to check a claimed skill against its evidence. Input: `skill`, an id, canonical name or address; optional `limit`, `cursor`. Returns `skill`, `evidence` and `page`; a profile's claim arrives via Skills.Skill with its level, an evidence row via Evidence.Skill. Attributes are verbatim.

Discovered
get_entity

One entity as structured data: fields, sections, tables, references both ways. Use to reason over one; for its page as written use fetch. Input: `id` or address, where its page sits, or `type` and `name`; an ambiguous name is refused with candidate ids. Returns `entity`, by id. Reference lists hold at most 50 edges; `referenceCounts` gives totals, list_references the rest.

Discovered
list_checks

The checks the model's own gate runs, from the checker release this server was built with. Use to see which rules a script enforces and which are left to a reader. No input. Returns `checks`, each with `name`, `rule`, `title` and what it `reports`, a `failure` or a `note` that fails nothing, and `ranBy`. This server runs none of them.

Discovered
list_entities

Entities with their frontmatter's short facts, in address order or newest first. Use to browse, or for what runs on a date, came last or has a value; to find by words use search. Input: optional `type`, `owner`, `order`, `on`, `by`, `where`, `fields`, `limit`, `cursor`. Returns `entities` with `fields`, and `page`; follow `page.nextCursor` while `page.hasMore`.

Discovered
list_references

The model's edges, filtered and paged. Use to inspect one entity's relations or one kind of reference without taking whole entities. Optional `entity` (an id or address), `direction` (out, in, both; needs `entity`), `via`, `type` (the far end's type, or either end's without `entity`), `limit`, `cursor`. Returns `edges`, each `from`, `via`, `to`, `attrs`, and `page`.

Discovered
list_rules

The vocabulary's conventions the model is held to, R0 onwards, from its core's CONVENTIONS.md. Use to resolve a number a schema or refusal cites, such as R9. A company's own rules are entities of type `rule`: list_entities and get_entity. No input. Returns `tagline`, the file's `url`, and `rules`, each with `rule`, `title` and `part`; describe_rule gives one rule's text.

Discovered
list_types

Every type the model's schemas declare. Use first, to learn which types exist before listing or describing one. No input. Returns `types`, each with `type`, `name`, `tagline`, `owner` (the type it nests under, or null) and `count`, the entities it holds.

Discovered
search

Find entities by words, substring or exact name. `match: "words"` needs every query word's stem in name, tagline, fields, sections or cells; `"text"` (default) is a case-insensitive substring over the same; `"name"` the exact canonical name. Optional `type`, `owner`, `limit`, `cursor`. Returns `results` with `id`, `title`, `type`, `matched`, `words` in words mode, and `page`: name matches first, then a listing.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected340 ms14