What is kerberos AGENTS.md?

Project-specific instructions for AI coding assistants working on a Node.js native add-on that provides Kerberos authentication for the MongoDB driver. Kerberos is a network login system that lets clients prove their identity to a service.

Use them when installing or rebuilding the add-on, changing its Node.js or C++ wrapper, running authentication tests, linting, formatting, or regenerating its documentation.

They explain the required native build dependencies, authentication setup, test requirements, and formatting commands for both JavaScript and C++ code.

How mongodb-js/kerberos configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to mongodb-js/kerberos. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/mongodb-js/kerberos/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/mongodb-js/kerberos

Made for: Codex, OpenCode.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/mongodb-js/kerberos/agents-md/github.svg)](https://agentmods.dev/instructions/mongodb-js/kerberos/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/mongodb-js/kerberos/agents-md"><img src="https://agentmods.dev/badge/instructions/mongodb-js/kerberos/agents-md/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/mongodb-js/kerberos/agents-md"><img src="https://agentmods.dev/badge/instructions/mongodb-js/kerberos/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 854 This file is loaded in full into every session.

When invoked 854 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00854	$0.00854
Opus 5.5	$0.00342	$0.00342
Sonnet 5.5	$0.00171	$0.00171
Haiku 4.5	$0.00085	$0.00085

Measured 2mo ago against content hash b30dad3260f6, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

kerberos AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

AGENTS.md · 47 lines

How it starts

The opening of the file, as written. The whole thing — 47 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Instructions for AI coding agents working in this repository. This file is the source of truth. Tool-specific files (e.g. CLAUDE.md) should only import it.

Project Overview

kerberos is a Node.js native addon providing Kerberos/GSSAPI authentication, used primarily by the MongoDB Node.js driver for GSSAPI auth. The C++ addon (node-addon-api / N-API 9) wraps GSSAPI on Unix and SSPI on Windows. On install, prebuild-install looks for a prebuilt addon binary, falling back to a source build via node-gyp rebuild (requires system Kerberos dev headers, e.g. libkrb5-dev, on Unix).

Commands

All scripts from package.json:

npm install — installs deps and compiles the addon.
npx node-gyp rebuild — recompile the addon only.
npm test — run mocha tests. Requires a compiled addon and a reachable KDC (configured via KERBEROS_USERNAME/KERBEROS_PASSWORD/KERBEROS_REALM/KERBEROS_HOSTNAME env vars).
npm run check:lint — lint JS/TS.
npm run format-js — eslint --fix.
npm run format-cxx — clang-format the C++ sources in src/.
npm run docs — regenerate README.md from JSDoc in lib/index.js (never edit README.md directly, edit etc/README.hbs or the JSDoc).
npm run precommit — check-clang-format. Verifies C++ formatting, and is invoked by the pre-commit hook.
npm run prepare — points core.hooksPath at .githooks/ so the tracked pre-commit hook is active. Runs automatically on npm install in a clone. It does not run for downstream consumers installing the published package.
npm run prebuild — build prebuilt addon binaries (prebuild --runtime napi --strip --verbose --all). Used by CI and release, rarely run locally.

Structure

src/ — C++ addon. kerberos.cc defines the N-API bindings.
src/unix/ — GSSAPI implementation.
src/win32/ — SSPI implementation.
lib/index.js — entrypoint: loads the compiled .node binary and exports promisified wrappers plus GSS flag/OID constants.
index.d.ts — the public types.
binding.gyp — node-gyp config. Selects unix vs win32 sources per platform.
test/ — mocha tests, plus test/bundling/webpack for bundler compatibility.

Read the full file on GitHub · 47 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

2mo ago First seen · 47 lines · 854 tokens per session scan A b30dad3260f6

Subscribe to this mod's changes

kerberos AGENTS.md is an instructions file published in the GitHub repository mongodb-js/kerberos (177 stars, last pushed today), licensed Apache-2.0. It adds 854 tokens to every session, about $0.0034 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

MongoDB authentication gssapi gssapi-authentication node-js nodejs

kerberos AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
kerberos AGENTS.mdmongodb-js/kerberos	Instructions file	177	today	Apache-2.0	A	854	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	today	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	today	MIT	A	4,680	Codex, OpenCode
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vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	275k	2d ago	MIT	A	4,313	Codex, OpenCode

kerberos: Instructions file for Codex