periscope-mcp: Instructions file for Codex

AGENTS.md

periscope-mcp AGENTS.md is an instructions file for Codex, OpenCode from segentic-lab/periscope-mcp. It costs 4,571 tokens per session, scanned C, original, AGPL-3.0.

Project instructions for using periscope-mcp to test websites and web apps. They describe its main model, normal testing workflows, debugging, and visual or responsive checks.

In plain words
What is it for?
Running website tests, checking visual layouts and mobile responsiveness, debugging page problems, and using periscope-mcp correctly.
Why use it?
They help coding agents follow the project's intended testing process and diagnose broken pages consistently.

Instructions file for CodexOpenCode

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

This is segentic-lab/periscope-mcp's own configuration. It tells Codex and OpenCode how to work on periscope-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 periscope-mcp configures →

Reuse

Borrowing it

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

README.md
[![agentmods](https://agentmods.dev/badge/instructions/segentic-lab/periscope-mcp/agents-md/github.svg)](https://agentmods.dev/instructions/segentic-lab/periscope-mcp/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/segentic-lab/periscope-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/segentic-lab/periscope-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.

agentmods 80×15 button for periscope-mcp AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/segentic-lab/periscope-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/segentic-lab/periscope-mcp/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 4,571 This file is loaded in full into every session.
When invoked 4,571 The same file — it is already loaded in full.
Security scan C 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 $0.04571 $0.04571
Opus 5.5 $0.01828 $0.01828
Sonnet 5.5 $0.00914 $0.00914
Haiku 4.5 $0.00457 $0.00457

Measured 2mo ago against content hash dcd34e3a1cae, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade C, and why

periscope-mcp AGENTS.md scanned grade C with 1 finding 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.

Hidden instructionshighPrompt injection

Directives inside HTML comments, invisible characters or bidirectional overrides are read by the model and not by the person reviewing the file.

<!-- Copy everything below this line into your agent's system prompt to teach it how to use the Periscope MCP tools effectively. -->
AGENTS.md · 317 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

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. 2mo ago First seen · 317 lines · 4,571 tokens per session scan C dcd34e3a1cae

Subscribe to this mod's changes

periscope-mcp AGENTS.md is an instructions file published in the GitHub repository segentic-lab/periscope-mcp (10 stars, last pushed 3mo ago), licensed AGPL-3.0. It adds 4,571 tokens to every session, about $0.0183 per session on Opus 5.5. A static security scan graded it C with 1 finding (hidden instructions). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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