# DiffCI (remote · diffci.com)

Change-aware CI validation and affected-test guidance for coding agents.

- Trust score: 72/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-26

## Components

- remote · `diffci.com`: 72/100 (this document), [markdown](https://verifymcp.io/servers/diffci-diffci/mcp-v1.md), [page](https://verifymcp.io/servers/diffci-diffci/mcp-v1)
- npm · `@diffci.com/diffci`: 39/100, [markdown](https://verifymcp.io/servers/diffci-diffci/diffci-com-diffci.md), [page](https://verifymcp.io/servers/diffci-diffci/diffci-com-diffci)

## Channel facts

- Endpoint: `https://diffci.com/mcp/v1`
- Transports: `streamable-http`
- Auth: `none`
- Version: `0.2.11`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, 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 2026-09-26.

- **Endpoint Security**: 74/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one.
  - HTTPS is enforced; there's no plaintext access path.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 78/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 283 tokens (~56/item across 5 items; 3 tools + 2 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 3/100
  - Stability observed for 1 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 3 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

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

DiffCI is a hosted endpoint at https://diffci.com/mcp/v1, so there is nothing to install locally. 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 --transport http diffci-diffci 'https://diffci.com/mcp/v1'
```

### Cursor

```json
{
  "mcpServers": {
    "diffci-diffci": {
      "url": "https://diffci.com/mcp/v1"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "diffci-diffci": {
      "type": "http",
      "url": "https://diffci.com/mcp/v1"
    }
  }
}
```

### Codex

```toml
[mcp_servers.diffci-diffci]
url = "https://diffci.com/mcp/v1"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "diffci-diffci": {
      "type": "remote",
      "url": "https://diffci.com/mcp/v1",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add diffci-diffci --url 'https://diffci.com/mcp/v1' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  diffci-diffci:
    url: "https://diffci.com/mcp/v1"
```

### Netclaw

```json
{
  "McpServers": {
    "diffci-diffci": {
      "Transport": "http",
      "Url": "https://diffci.com/mcp/v1"
    }
  }
}
```

### Vellum

```bash
assistant mcp add diffci-diffci -t streamable-http -u 'https://diffci.com/mcp/v1'
```

### Other

```json
{
  "mcpServers": {
    "diffci-diffci": {
      "type": "http",
      "url": "https://diffci.com/mcp/v1"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## 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.

### 2026-09-26 (score 72, 0)

- [functional improvement] Stability: unverified → 0.03

### 2026-09-25 (score 72)

First indexed and scored.

## MCP tools (3)

### `diffci_validation_plan` (~98 tokens)

Create a local DiffCI validation plan

Plan change-aware CI validation, affected-test selection, test impact analysis, or GitHub Actions workflow checks. Returns a safe local DiffCI command without accessing the checkout or executing it.

Input parameters:

- `action` (string): Validation action. Defaults to check.
- `platform` (string): Shell used only to render the display command. Defaults to posix.
- `repo` (string): Optional local repository path to pass as a single --repo argument.

### `diffci_interpret_report` (~60 tokens)

Interpret a DiffCI observation report

Validate and summarize a DiffCI observation report, including selective or full mode, affected-test counts, fallbacks, non-interference evidence, and the conservative next action.

Input parameters:

- `report` (object, required): A diffci.observation.v1 JSON report.

### `diffci_verify_workflow_text` (~60 tokens)

Check a GitHub Actions workflow for DiffCI isolation

Perform a stateless preliminary safety check of GitHub Actions YAML: dedicated observer job, continue-on-error, dependency isolation, read-only permissions, and immutable DiffCI references.

Input parameters:

- `workflow` (string, required): One GitHub Actions workflow YAML document.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/diffci-diffci/mcp-v1#diagnostics

## Score history

- 2026-09-26: 72
- 2026-09-25: 72

## Common questions

### What is the DiffCI MCP server?

DiffCI is an MCP server listed in the public MCP registry as io.github.DiffCI/diffci. Change-aware CI validation and affected-test guidance for coding agents. This page covers its hosted endpoint (https://diffci.com/mcp/v1).

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

DiffCI scores 72 out of 100 on VerifyMCP. 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 DiffCI MCP server expose?

DiffCI exposes 3 tools: diffci_validation_plan, diffci_interpret_report, diffci_verify_workflow_text. Their descriptions and schemas cost roughly 218 tokens of context every time the server is loaded.

### Does the DiffCI MCP server require authentication?

No. We connected to DiffCI without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

### Is the DiffCI MCP server still maintained?

DiffCI is still listed as active in the MCP registry. We last reached this channel on 26 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- Remote endpoint: https://diffci.com/mcp/v1
- Repository: https://github.com/DiffCI/DiffCI.com
- Website: https://diffci.com/mcp-server
- Changelog RSS feed: https://verifymcp.io/servers/diffci-diffci/mcp-v1.xml
- Changelog JSON feed: https://verifymcp.io/servers/diffci-diffci/mcp-v1.json
- HTML version of this page: https://verifymcp.io/servers/diffci-diffci/mcp-v1