Use it when building, type-checking, testing, or modifying posokanei-mcp, especially its TypeScript source, MCP tools, API behavior, and test setup.

It helps contributors make changes in the correct source files and verify them with the project’s real checks. The read-only rule and mocked tests reduce the risk of unintended writes or dependence on a live service.

How charistas/posokanei-mcp configures Codex and OpenCode

Q: What is posokanei-mcp AGENTS.md?

Repository guidance for posokanei-mcp, a read-only MCP server that provides supermarket product and price data from PosoKanei. It documents the project commands, source conventions, tests, and limits on API access.

Reuse

Borrowing it

Nothing to install: this file belongs to charistas/posokanei-mcp. 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/charistas/posokanei-mcp/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/charistas/posokanei-mcp

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/charistas/posokanei-mcp/agents-md/github.svg)](https://agentmods.dev/instructions/charistas/posokanei-mcp/agents-md)

Your own site

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

Per session 779 This file is loaded in full into every session.

When invoked 779 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	$0.00779	$0.00779
Opus 5	$0.00390	$0.00390
Sonnet 5	$0.00156	$0.00156
Haiku 4.5	$0.00078	$0.00078

Measured 9d ago against content hash 62f2688ad517, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

posokanei-mcp 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 9d 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 · 88 lines

How it starts

The opening of the file, as written. The whole thing — 88 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Repository Guidance

Project Overview

posokanei-mcp is an unofficial read-only MCP server for supermarket product and price data from PosoKanei.

It is published as the posokanei-mcp npm package and registered as io.github.charistas/posokanei-mcp in the MCP Registry.

This project is not affiliated with, endorsed by, or operated by PosoKanei, gov.gr, or any Greek public authority.

Commands

Requires Node.js >=20.

npm install
npm run build
npm run typecheck
npm test

There is no lint script. Do not invent one as a required verification gate.

The test suite mocks PosoKanei API calls. Do not add required tests that depend on live PosoKanei network access.

Source Conventions

Edit src/, not dist/. dist/ is generated and ignored.
Keep TypeScript ESM style consistent with the existing files.
Prefer Node built-ins and the official MCP SDK over new runtime dependencies.
Keep changes small and directly tied to the task.
If adding a runtime dependency is unavoidable, justify license compatibility, maintenance, security posture, and install footprint.

MCP And API Safety

Keep the server read-only.
Do not add write, form-submission, account, auth-bypass, or mutation tools without an explicit design discussion.
Treat PosoKanei endpoints as public but undocumented. Keep requests modest, cache-friendly, and rate-limited.
Bound list, tree, search, and comparison responses so a single tool call cannot flood the client with huge JSON.
Tool descriptions must be precise and must not imply official government affiliation.
Keep API errors visible for transient or service-level failures.
Only treat missing resources as unmatched user input when the API clearly returns a not-found condition.
Preserve explicit constructor options over environment defaults.
Keep rate limiting serialized for concurrent requests.
Keep cache behavior deterministic and easy to disable in tests.

Tests And Docs

For behavior changes, add or update focused tests.
For MCP tool or schema changes, update MCP server tests and the README tool table.
Update README.md when installation, tools, environment variables, publishing, or public behavior changes.
Keep package.json#mcpName and server.json#name identical.
Keep server.json package version aligned with package.json#version.
Keep server.example.json aligned with server.json unless it intentionally demonstrates placeholders.

Read the full file on GitHub · 88 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.

9d ago First seen · 88 lines · 779 tokens per session scan A 62f2688ad517

Subscribe to this mod's changes

posokanei-mcp AGENTS.md is an instructions file published in the GitHub repository charistas/posokanei-mcp (3 stars, last pushed 6d ago), licensed MIT. It adds 779 tokens to every session, about $0.0039 per session on Opus 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 2026-08-31.

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AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.

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vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

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posokanei-mcp: Instructions file for Codex