# CEDRUS (pypi · cedrus-mcp)

Reasoning scaffolding that supercharges your small AI: an argument-mapping MCP server

- Trust score: 67/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-20

## Components

- pypi · `cedrus-mcp`: 67/100 (this document), [markdown](https://verifymcp.io/servers/cedrus-mcp-cedrus-mcp/cedrus-mcp.md), [page](https://verifymcp.io/servers/cedrus-mcp-cedrus-mcp/cedrus-mcp)

## Channel facts

- Registry: `pypi`
- Package: `cedrus-mcp`
- Version: `2.0.1`
- Transport: `stdio`

## Trust breakdown

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. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-09-20.

- **Supply Chain Security**: 100/100
  - No malware found by supply-chain analysis.
  - No known CVEs affecting this package version or its production dependencies.
  - Runs hatchling.build at install time, a recognised native-build step with no shell scripting around it.
  - 1 of 30 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 32/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - License check failed: the license (GNU Affero General Public License v3 or later (AGPLv3+)) isn't a recognized OSI-approved license.
  - Actively maintained (last published 1 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 89/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (excellent).
  - Tool/resource definitions use about 1071 tokens (~107/item across 10 items; 8 tools + 2 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 0/100
  - Stability not yet verified: not enough scan history yet (needs a 30-day window).
- **Tool Coverage**: 71/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 0% of tool parameters carry a description.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Tool Safety**: 75/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - 0 of 2 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "unlink" implies "unlink" and declares no destructiveHint at all, which the MCP spec reads as destructive by default.
  - An AI judge read all 10 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a current MCP spec version (2026-07-28).

**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.

## Install

### How do I install the CEDRUS MCP server?

CEDRUS runs locally as a PyPI package, launched with uvx cedrus-mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add cedrus-mcp-cedrus-mcp -- uvx cedrus-mcp
```

### Cursor

```json
{
  "mcpServers": {
    "cedrus-mcp-cedrus-mcp": {
      "command": "uvx",
      "args": [
        "cedrus-mcp"
      ]
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "cedrus-mcp-cedrus-mcp": {
      "command": "uvx",
      "args": [
        "cedrus-mcp"
      ]
    }
  }
}
```

### Codex

```bash
codex mcp add cedrus-mcp-cedrus-mcp -- uvx cedrus-mcp
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "cedrus-mcp-cedrus-mcp": {
      "type": "local",
      "command": [
        "uvx",
        "cedrus-mcp"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add cedrus-mcp-cedrus-mcp --command uvx --arg cedrus-mcp
```

### Hermes

```yaml
mcp_servers:
  cedrus-mcp-cedrus-mcp:
    command: "uvx"
    args: ["cedrus-mcp"]
```

### Netclaw

```json
{
  "McpServers": {
    "cedrus-mcp-cedrus-mcp": {
      "Transport": "stdio",
      "Command": "uvx",
      "Arguments": [
        "cedrus-mcp"
      ]
    }
  }
}
```

### Vellum

```bash
assistant mcp add cedrus-mcp-cedrus-mcp -t stdio -c uvx -a cedrus-mcp
```

### Other

```json
{
  "mcpServers": {
    "cedrus-mcp-cedrus-mcp": {
      "command": "uvx",
      "args": [
        "cedrus-mcp"
      ]
    }
  }
}
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-09-19 (score 67, +15)

- [security improvement] Malware scan: unverified → pass

### 2026-09-18 (score 52)

First indexed and scored.

## MCP tools (8)

### `show` (~52 tokens)

Show the whole argument map: its claims, its arguments and all relations.

Call this whenever you need to see the current map. Its output replaces any
earlier show output, so you only ever need the latest one.

Output parameters:

- `result` (string)

### `add_claim` (~134 tokens)

Add a claim: the statement being debated, or a general principle arguments rely on.

Add a claim first; arguments need something to respond to. A claim that responds to
nothing is a root claim. To make a claim support or attack something, use link
afterwards.

Args:
    label: A short title of a few words, e.g. "Legalisation of soft drugs".
    text: The claim written out as one statement.

Returns:
    The new ID (C1, C2, …) and the state of the map.

Input parameters:

- `label` (string, required)
- `text` (string, required)

Output parameters:

- `result` (string)

### `add_argument` (~216 tokens)

Add a new argument that responds to a claim or argument already in the map.

Args:
    target: The ID the argument responds to, e.g. "C1" or "A7".
    relation: How it responds to the target. One of:
        "supports" - the argument gives a reason for the target;
        "attacks" - the argument gives a reason against the target;
        "undercuts" - the argument says the target's reasons do not lead to its
        conclusion, without denying that those reasons are true. The target of an
        undercut must be an argument, not a claim.
    label: A short title of a few words, e.g. "Tax revenue".
    text: The argument written out in full.

Returns:
    The new ID (A1, A2, …) and the state of the map.

Input parameters:

- `label` (string, required)
- `relation` (string, required)
- `target` (string, required)
- `text` (string, required)

Output parameters:

- `result` (string)

### `link` (~123 tokens)

Relate two claims or arguments that are already in the map.

Use this when one argument responds to more than one thing, or when a claim
supports or attacks something. If the two are already related, this changes the
relation to the new type.

Args:
    source: The ID that does the supporting, attacking or undercutting.
    relation: "supports", "attacks" or "undercuts".
    target: The ID being responded to.

Input parameters:

- `relation` (string, required)
- `source` (string, required)
- `target` (string, required)

Output parameters:

- `result` (string)

### `unlink` (~99 tokens)

Remove the relation that goes from source to target.

An argument must keep at least one target, so its last relation cannot be removed.
A claim may lose all of its relations. To move an argument, link it to its new
target first and unlink the old one afterwards.

Args:
    source: The ID the relation starts at.
    target: The ID the relation points to.

Input parameters:

- `source` (string, required)
- `target` (string, required)

Output parameters:

- `result` (string)

### `edit` (~101 tokens)

Change the label and/or the text of a claim or an argument.

The ID and every relation stay as they are.

Args:
    id: The ID to change, e.g. "A7".
    label: A new short title. Leave empty to keep the current one.
    text: A new full text. Leave empty to keep the current one.

Input parameters:

- `id` (string, required)
- `label` (string)
- `text` (string)

Output parameters:

- `result` (string)

### `delete` (~107 tokens)

Delete a claim or an argument, together with its relations.

The ID is never given to a new item. If some arguments respond only to this one,
the deletion is refused and they are named, because they would be left with nothing
to respond to.

Args:
    id: The ID to delete, e.g. "A7".
    with_replies: Set to true to delete those arguments as well.

Input parameters:

- `id` (string, required)
- `with_replies` (boolean)

Output parameters:

- `result` (string)

### `new_map` (~62 tokens)

Start a new, empty argument map, e.g. to map a different issue.

Only call this when you are done with the current map: it is cleared. IDs start
again at C1 and A1, so IDs from the old map no longer apply.

Output parameters:

- `result` (string)

## Diagnostics

Captured diagnostic sections: Provenance, Install scripts, Dependencies. The full working is on the page: https://verifymcp.io/servers/cedrus-mcp-cedrus-mcp/cedrus-mcp#diagnostics

## Score history

- 2026-09-20: 67
- 2026-09-19: 67
- 2026-09-18: 52

## Common questions

### What is the CEDRUS MCP server?

CEDRUS is an MCP server listed in the public MCP registry as io.github.cedrus-mcp/cedrus-mcp. Reasoning scaffolding that supercharges your small AI: an argument-mapping MCP server. This page covers its PyPI package (cedrus-mcp).

### Is the CEDRUS MCP server safe to use?

CEDRUS scores 67 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 20 September 2026. 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 CEDRUS MCP server expose?

CEDRUS exposes 8 tools: show, add_claim, add_argument, link, unlink, and 3 more. Their descriptions and schemas cost roughly 894 tokens of context every time the server is loaded.

### Is the CEDRUS MCP server still maintained?

CEDRUS is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- PyPI project: https://pypi.org/project/cedrus-mcp/
- Socket report: https://socket.dev/pypi/package/cedrus-mcp
- Repository: https://github.com/cedrus-mcp/cedrus-mcp
- Changelog RSS feed: https://verifymcp.io/servers/cedrus-mcp-cedrus-mcp/cedrus-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/cedrus-mcp-cedrus-mcp/cedrus-mcp.json
- HTML version of this page: https://verifymcp.io/servers/cedrus-mcp-cedrus-mcp/cedrus-mcp