What is Agent-Span AGENTS.md?

A set of coding instructions for AgentSpan, an asynchronous Rust web-access gateway for AI agents. It explains the repository layout and the commands used to build, test, lint, format, and run its services.

It is for working on AgentSpan's routing, caching, authentication, API, channels, health checks, and Python SDK, including adding a communication channel or an MCP tool. MCP is a standard way for AI assistants to connect to tools.

It gives a developer a map of a multi-package Rust repository and makes the expected checks explicit. This reduces guesswork when changing code or adding integrations.

How oxbshw/Agent-Span configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to oxbshw/Agent-Span. 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/oxbshw/Agent-Span/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/oxbshw/Agent-Span

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/oxbshw/agent-span/agents-md/github.svg)](https://agentmods.dev/instructions/oxbshw/agent-span/agents-md)

Your own site

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

Per session 700 This file is loaded in full into every session.

When invoked 700 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	$0.00700	$0.00700
Opus 5.5	$0.00280	$0.00280
Sonnet 5.5	$0.00140	$0.00140
Haiku 4.5	$0.00070	$0.00070

Measured 2mo ago against content hash fb32326c26d7, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

Agent-Span 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 · 61 lines

How it starts

The opening of the file, as written. The whole thing — 61 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

AgentSpan is an async-Rust web access gateway for AI agents. This file is for AI coding assistants (Claude Code, Cursor, Codex) working in this repo.

Build & test

cargo test --workspace                    # run all tests
cargo clippy --workspace --all-targets -- -D warnings   # lint
cargo fmt --all -- --check                # format check
cargo run --bin agentspan -- serve         # start the API on :8080
cargo run --bin agentspan-mcp              # start the MCP server (stdio)

Python SDK: pip install -e sdk/python[dev] then pytest -q in sdk/python/.

Crate layout

Crate	What lives here
`agentspan-core`	`Channel`/`Backend` traits, types, config, errors
`agentspan-probe`	Command execution + 6-state health classification
`agentspan-router`	Backend selection, retry, circuit breaker, adaptive routing
`agentspan-cache`	3-tier cache (memory/disk/Redis), singleflight, optimizer
`agentspan-auth`	API keys (SHA-256), tenants, RBAC, rate limiting, audit
`agentspan-channels`	All 52 channel implementations + registry
`agentspan-api`	Axum REST server, SSE, OpenAPI spec, middleware
`agentspan-mcp`	MCP server (stdio + HTTP), 91 tools
`agentspan-cli`	The `agentspan` binary — install, doctor, serve, skill, etc.

Adding a channel

Copy crates/agentspan-channels/src/hackernews.rs (free API) or spotify.rs (OAuth) as a template.
Implement Channel + Backend traits. Use BackendRouter for fallback.
Register in src/lib.rs (module + re-export) and src/registry.rs.
Add MCP tools in crates/agentspan-mcp/src/tools.rs.
Add a format rule in crates/agentspan-cli/src/commands/format.rs.
Run cargo test -p agentspan-channels — the registry count test will tell you the expected count.

Adding an MCP tool

Add a ToolDef entry in crates/agentspan-mcp/src/tools.rs. The channel field must match a registered channel name. Use Op::Read for URL-based fetch, Op::Search for keyword queries, Op::Doctor for health.

Read the full file on GitHub · 61 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 · 61 lines · 700 tokens per session scan A fb32326c26d7

Subscribe to this mod's changes

Agent-Span AGENTS.md is an instructions file published in the GitHub repository oxbshw/Agent-Span (45 stars, last pushed 2mo ago), licensed MIT. It adds 700 tokens to every session, about $0.0028 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.

LLM ai-agents ai-tools api gateway mcp

Agent-Span AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
Agent-Span AGENTS.mdoxbshw/Agent-Span	Instructions file	45	2mo ago	MIT	A	700	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

Agent-Span: Instructions file for Codex