browser-agent AGENTS.md

browser-agent AGENTS.md is an instructions file for Codex, OpenCode from visnia-ai/browser-agent. It costs 529 tokens per session, scanned A, original, MIT.

A set of project instructions for developing visnia-ai/browser-agent. It defines where important code belongs, how browser page structure and element references must be handled, and how providers and settings are organized.

In plain words
What is it for?
Use it while modifying browser-agent code, especially its agents, browser projections, configuration, providers, or public core APIs. It also guides verification and safe handling of authentication.
Why use it?
It gives coding agents consistent rules for changing the project without breaking its internal contracts. It also identifies the project's authoritative sources and boundaries.

Instructions file for CodexOpenCode

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/visnia-ai/browser-agent/agents-md
Clone the repo
git clone --depth 1 https://github.com/visnia-ai/browser-agent

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 browser-agent AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/visnia-ai/browser-agent/agents-md.svg)](https://agentmods.dev/instructions/visnia-ai/browser-agent/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/visnia-ai/browser-agent/agents-md"><img src="https://agentmods.dev/badge/instructions/visnia-ai/browser-agent/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 529 This file is loaded in full into every session.
When invoked 529 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.00529 $0.00529
Opus 5 $0.00264 $0.00264
Sonnet 5 $0.00106 $0.00106
Haiku 4.5 $0.00053 $0.00053

Measured 5d ago against content hash 7c77da96f6eb, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

browser-agent 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 5d 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 · 33 lines

How it starts

The opening of the file, as written. The whole thing — 33 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Architecture

  • Keep reusable src/core/ APIs configurable through explicit typed inputs and dependency injection. Do not make core entrypoints depend on YAML files, CLI arguments, or implicit environment configuration.
  • Keep CLI YAML parsing and validation centralized in src/utils.ts (loadConfig).
  • Expose new public core surfaces through src/core/index.ts and src/core/types.ts.
  • Route provider execution through src/agents/providers/ai-sdk.ts; do not add provider-specific router implementations.
  • Put runtime-configurable flags in src/config-feature-flags.ts and internal static flags in src/featureFlags.ts.

Model and Projection Contracts

  • The harness uses only the canonical semantic projection from src/browser/semantic-projection.ts; do not add alternate semantic serializers or simplified-DOM fallbacks.
  • Actions targeting page elements must use opaque ref values from the current canonical semantic projection and resolve them through the semantic ref registry.
  • Keep the standalone simplified-DOM library isolated under src/browser/simplify-dom.ts and src/browser/simplify-dom-utils/. Canonical harness code in src/agents/, src/core/, and src/auth/ must not import it or depend on its identifiers.
  • Changes to semantic projection structure must preserve ref extraction, action resolution, projection-history reconstruction, and prompt contracts.

Authentication Safety

  • Treat changes to auth runtime, executor integration, prompts, config parsing, or auth input handling as security-sensitive.
  • Never expose real credentials to a model, prompt payload, screenshot, semantic projection, history, logs, thrown errors, or serialized results.
  • Match the current URL to a configured auth domain before decrypting its identifier or password. Keep domain, identifier, and password encrypted independently.
  • Plaintext credentials are allowed only at direct runtime entrypoints and must be encrypted immediately. YAML configuration must accept encrypted credentials only.
  • Models may inspect only the redacted semantic projection to identify auth controls. Credential lookup, entry, and submission must remain in runtime code.
  • Keep protected auth refs redacted and suppress screenshots while sensitive values may be present.
  • When automated auth cannot proceed safely, return it as unhandled and use manual takeover only when enabled.
  • Cover auth behavior changes with unit tests and maintain or extend the local fixture/e2e coverage.

Read the full file on GitHub · 33 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. 5d ago First seen · 33 lines · 529 tokens per session scan A 7c77da96f6eb

Subscribe to this mod's changes

browser-agent AGENTS.md is an instructions file published in the GitHub repository visnia-ai/browser-agent (21 stars, last pushed 7d ago), licensed MIT. It adds 529 tokens to every session, about $0.0026 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 2026-08-30.