pagespeed-insights-mcp: Instructions file for Codex

AGENTS.md

pagespeed-insights-mcp AGENTS.md is an instructions file for Codex, OpenCode from Considus/pagespeed-insights-mcp. It costs 1,097 tokens per session, scanned A, original, Apache-2.0.

Repository instructions for changing the pagespeed-insights-mcp project. They define a process of isolating work on a branch, building it, proving the result with evidence, and submitting a pull request.

In plain words
What is it for?
Use them when contributing to this repository, from creating a branch through testing the change and preparing its pull request.
Why use it?
They reduce accidental changes on the wrong branch and make each proposed change easier to verify.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

This is Considus/pagespeed-insights-mcp's own configuration. It tells Codex and OpenCode how to work on pagespeed-insights-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything pagespeed-insights-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Considus/pagespeed-insights-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/Considus/pagespeed-insights-mcp/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/Considus/pagespeed-insights-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.

agentmods badge for pagespeed-insights-mcp AGENTS.md

README.md
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Your own site
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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.

agentmods 80×15 button for pagespeed-insights-mcp AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/considus/pagespeed-insights-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/considus/pagespeed-insights-mcp/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 1,097 This file is loaded in full into every session.
When invoked 1,097 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.01097 $0.01097
Opus 5 $0.00549 $0.00549
Sonnet 5 $0.00219 $0.00219
Haiku 4.5 $0.00110 $0.00110

Measured yesterday against content hash 140a20522813, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-19, from the pricing page.

Security

Grade A, and why

pagespeed-insights-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 yesterday.

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 · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent notes

For a coding agent working in this repo. CONTRIBUTING.md is the human document and it is not duplicated here; read it first for the ground rules and the release order. This file is the part an agent needs and a person already knows.

Every task moves through four beats: isolate on a branch, build, prove with evidence, ship a PR carrying that evidence.

Isolate

Branch from origin/main by name, never from wherever HEAD is sitting, and check nobody is already on the work:

git fetch origin
gh pr list -R Considus/pagespeed-insights-mcp
git checkout -b <type>/<short-name> origin/main

If an open PR touches the same files, build on it or say so and stop. Stage by explicit path. Never git add -A.

Build

Read CONTRIBUTING.md before writing. Three things there are constraints rather than preferences, and a change that breaks one is rejected however good the rest is.

  • Standard library only, with no optional-dependency escape hatch. This is what lets someone who does not use a terminal download the package and run it, and it is why the service-account credential was dropped for an API key.
  • No number without its uncertainty. Every figure is a median across distinct analyses with its min-max spread beside it, and runs PSI served from cache are dropped and counted.
  • Lab and field stay separate. Lighthouse is a simulation, CrUX is what real people got. They disagree by an order of magnitude and merging them destroys the only honest thing here.

Python 3.9 is the floor. CI runs 3.9 and 3.12 on Linux, macOS and Windows. A 3.10-only construct (match, a runtime-evaluated X | Y annotation, zip(strict=), itertools.pairwise, tomllib, dataclass(slots=)) passes on your interpreter and fails only in the 3.9 leg. Windows is in the matrix on purpose: being installable there without a compiled dependency is a property that would regress silently.

manifest.json is generated. The version lives in pagespeed_insights/__init__.py and the tool list lives in the package. ./build-mcpb.py --sync writes both across. Never hand-edit the manifest. Every tool needs a title and the right readOnlyHint or destructiveHint; a directory submission is rejected without them, and report is the one tool that is not read-only because it writes a file.

Read the full file on GitHub · 67 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.

  1. yesterday First seen · 67 lines · 1,097 tokens per session scan A 140a20522813

Subscribe to this mod's changes

pagespeed-insights-mcp AGENTS.md is an instructions file published in the GitHub repository Considus/pagespeed-insights-mcp (0 stars, last pushed yesterday), licensed Apache-2.0. It adds 1,097 tokens to every session, about $0.0055 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 2026-09-18.

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