# Codeforces MCP Server (remote · codeforces-oj-mcp.lantangtang54.workers.dev)

Search Codeforces problems and inspect public problem metadata through the official Codeforces API.

- Trust score: 60/100 (medium)
- Change this week: +7
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-03

## Components

- remote · `codeforces-oj-mcp.lantangtang54.workers.dev`: 60/100 (this document), [markdown](https://verifymcp.io/servers/ketherworks-codeforces/codeforces-oj-mcp.md), [page](https://verifymcp.io/servers/ketherworks-codeforces/codeforces-oj-mcp)

## Channel facts

- Endpoint: `https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `0.1.0`

## 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 2026-08-03.

- **Endpoint Security**: 63/100
  - 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 not yet verified: we couldn't determine whether a plaintext access path exists.
  - 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**: 43/100
  - AI-judged instruction clarity (poor).
  - Tool/resource definitions use about 138 tokens (~34/item across 4 items; 4 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 27/100
  - Stability observed for 8 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **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.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### Claude

```bash
claude mcp add --transport http ketherworks-codeforces https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp
```

### Codex

```toml
[mcp_servers.ketherworks-codeforces]
url = "https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "ketherworks-codeforces": {
      "type": "remote",
      "url": "https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add ketherworks-codeforces --url https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  ketherworks-codeforces:
    url: "https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp"
```

### Other

```json
{
  "mcpServers": {
    "ketherworks-codeforces": {
      "type": "http",
      "url": "https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp"
    }
  }
}
```

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.

### 2026-08-03 (score 60, +1)

No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-08-01 (score 59, +1)

No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-31 (score 58, +3)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-30 (score 55, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-28 (score 54, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-27 (score 53, +1)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-26 (score 52)

First indexed and scored.

## MCP tools (4)

### `oj_capabilities` (~20 tokens)

Codeforces Provider Capabilities

Report audited Codeforces official API capabilities and unsupported operations.

### `oj_health` (~21 tokens)

Codeforces Provider Health

Return passive transport, schema, and persisted Codeforces upstream health.

### `oj_search_problems` (~61 tokens)

Search Codeforces Problems

Search official Codeforces problem metadata by id, title, or tag.

Input parameters:

- `limit` (integer, required)
- `platform` (string, required)
- `query` (string, required)
- `requestId` (string, required)
- `schemaVersion` (string, required)

### `codeforces_get_problem_metadata` (~36 tokens)

Get Codeforces Problem Metadata

Get official metadata only. This tool does not return a problem statement or submit code.

Input parameters:

- `nativeId` (string, required)

## Diagnostics

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

## Score history

- 2026-08-03: 60
- 2026-08-02: 59
- 2026-08-01: 59
- 2026-07-31: 58
- 2026-07-30: 55
- 2026-07-29: 54
- 2026-07-28: 54
- 2026-07-27: 53
- 2026-07-26: 52

## Links

- Remote endpoint: https://codeforces-oj-mcp.lantangtang54.workers.dev/mcp
- Repository: https://github.com/ketherworks/codeforces-mcp-server
- Changelog RSS feed: https://verifymcp.io/servers/ketherworks-codeforces/codeforces-oj-mcp/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/ketherworks-codeforces/codeforces-oj-mcp/changelog.json
- HTML version of this page: https://verifymcp.io/servers/ketherworks-codeforces/codeforces-oj-mcp