About Codna — repository intelligence
Codna is a repository intelligence tool for developers and coding agents, available as a CLI and MCP server. It maps code, triages issues, reviews pull requests, plans fixes, checks SARIF findings for reachability, and recalls local code memory.
Key features
- 01Repository mapping and issue triage
- 02Pull request review and fix planning
- 03Apply fixes and rerun tests
- 04SARIF finding reachability checks
- 05Offline local code recall
Use cases
- 01Locate files related to a reported issue
- 02Review a pull request and post findings
- 03Check which scanner findings are reachable
- 04Recall code from on-device memory
MCP support
Codna exposes five repository tools over an MCP stdio server: triage, security reachability, recall, fix planning, and bug reporting. Tool execution requires a free community login; some tools also require a provider key or GitHub token.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
uvx codnaANTHROPIC_API_KEYSecretProvider key for codna_fix's planner — any one of ANTHROPIC_API_KEY (Anthropic), OPENAI_API_KEY (OpenAI/ChatGPT), or GEMINI_API_KEY (Gemini) works (or store one with `codna key set <provider>`). Every tool also requires the one-time free `codna login` device authorization before executing; introspection (initialize/tools/list) needs no credentials.OPENAI_API_KEYSecretAlternative provider key (OpenAI/ChatGPT) for codna_fix's planner — see ANTHROPIC_API_KEY.GEMINI_API_KEYSecretAlternative provider key (Gemini) for codna_fix's planner — see ANTHROPIC_API_KEY.GITHUB_TOKENSecretWrite token, only for codna_fix with open_pr=true (opens a pull request) and codna_report_bug (files an issue).CODNA_API_KEYSecretCodna key from the one-time free `codna login` (device authorization, free community license). Required to execute any of the five tools; introspection (initialize/tools/list) needs none.Local servers need a runtime on your machine (e.g. Node.js 18+). Config file locations differ by client; see your client’s docs.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMECodna
Understand. Fix. Evolve.
Agents read your code. Codna understands it.
Codna maps a repository before it spends a token. It then reviews pull requests, fixes bugs and
proves which scanner findings are reachable. The same codna command runs on your machine, in the
GitHub Action and behind the GitHub App.
Runs on your machine or your cloud. Your code never leaves without your key.
Install
pip install codna # or: pipx install codna · uv tool install codna
codna --version
Python 3.12–3.13. Wheels for macOS on Apple silicon and Linux x86_64. git on your PATH.
Nothing else to install: no Node, Bun, Docker or server. The agent runtime ships inside the wheel.
Local commands need no Codna key. fix and review use your own model provider key, stored in
the OS keychain and never printed:
codna key set anthropic # also: openai, gemini, google, groq, mistral, openrouter, xai, cursor
Commands
codna triage . --issue "checkout total is wrong" # suspect files. Deterministic. 0 LLM tokens.
codna review . --pr 123 --post # findings with a verdict on the pull request
codna fix . --tests --apply --max-iterations 3 # patch, re-run your tests, re-fix until green
codna fix <git url> --ref <sha> --issue "…" --open-pr # push a branch and open a pull request
codna secure . --from-sarif results.sarif # which scanner findings are reachable. 0 LLM tokens.
codna fix prints the root cause, the impacted symbols, the blast radius, its confidence and a
regression risk. --open-pr needs a git URL and a GitHub write token. codna review posts one
inline comment per finding with severity, category and a suggestion block, and an Approve when the
diff is clean at medium and high. codna secure reads SARIF 2.1.0 from CodeQL, Semgrep, Snyk,
Trivy or any other scanner.
Other commands: init, status, doctor, login, key, impact, memory export, report.
Full reference: docs.codna.ai/reference/cli.
MCP server
Run Codna as a Model Context Protocol server over stdio — the same engine the CLI uses, inside Cursor, Claude Desktop, or your own agent:
pipx install "codna[mcp]" # or: pip install "codna[mcp]"
codna mcp # serve over stdio
codna mcp install --client cursor # optional: write the client config for you (or --client claude)
Five tools, each returning JSON; a failure comes back as codna_<tool> error: … text and never
crashes the server:
| Tool | What it does | Needs |
|---|---|---|
codna_triage | Understand a repo and locate the code relevant to an issue. Deterministic, 0 LLM tokens. | free codna login |
codna_secure | Prove which SARIF scanner findings (CodeQL, Semgrep, Snyk, Trivy) are reachable. Read-only, 0 LLM tokens. | free codna login |
codna_recall | Recall code from local on-device memory — semantic + lexical search, fully offline. | free codna login (which also installs the on-device runtime) |
codna_fix | Root-cause and plan a fix (read-only by default); with open_pr=true pushes a branch and opens a real PR. | free codna login + provider key (BYOK; + GITHUB_TOKEN for open_pr=true) |
codna_report_bug | File a bug, feature, or question to thyn-ai/feedback. | free codna login + GITHUB_TOKEN (else returns a pre-filled URL) |
Introspection (initialize/tools/list) needs no credentials. Executing any of the five tools
requires the one-time free community login (codna login — device authorization, free community
license) — fully offline thereafter. codna_fix additionally needs a provider key (BYOK, e.g.
ANTHROPIC_API_KEY); codna_report_bug needs GITHUB_TOKEN or it returns a pre-filled issue
URL; codna_recall additionally uses the on-device memory runtime that the same codna login
installs.
Full reference:
docs.codna.ai/guides/mcp.
Code memory
Code memory and recall run on your machine after a one-time free codna login (device
authorization), which also installs the signed on-device runtime. From then on, recall runs fully
offline: no key, no network calls. The optional
codna[memory] extra adds the on-device semantic reranker; without it, recall ranks lexically.
What leaves your machine
- Repository mapping, triage, recall and
impactrun offline. No model is involved. fixandreviewsend one issue-specific evidence bundle to the provider you chose, under your key. Not the repository.- Secret redaction is always on and cannot be turned off.
privacy.egress: fail-closedincodna.yamlrefuses to run tests without network denial and skips registry lookups during review.- Source distributions exclude runtime binaries, keys,
.envfiles and logs.
Links
- Homepage: https://codna.ai
- Documentation: https://docs.codna.ai
- Source (public mirror): https://github.com/thyn-ai/codna-cli
- Security: https://codna.ai/security
Comments
New to MCP?
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