What is service-agent?

A coding-agent guide for maintaining business-logic libraries inside a project's services/ directories. It covers domain rules, use cases, policies, and the interfaces services use to reach outside systems.

Use it when changing service code, service-level test fixtures, verification files, or a service's model.yaml declaration. It also helps when a service interface changes and must be coordinated with contract work.

It helps keep business logic separate from web servers and message-processing code. It also clarifies which files and checks belong to the service layer.

How openclosed-org/axum-harness configures Claude Code and Codex

Reuse

Borrowing it

Nothing to install: this file belongs to openclosed-org/axum-harness. 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/openclosed-org/axum-harness/main/.agents/skills/service-agent/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/openclosed-org/axum-harness

Made for: Claude Code, Codex.

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/skills/openclosed-org/axum-harness/service-agent/github.svg)](https://agentmods.dev/skills/openclosed-org/axum-harness/service-agent)

Your own site

<a href="https://agentmods.dev/skills/openclosed-org/axum-harness/service-agent"><img src="https://agentmods.dev/badge/skills/openclosed-org/axum-harness/service-agent/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/skills/openclosed-org/axum-harness/service-agent"><img src="https://agentmods.dev/badge/skills/openclosed-org/axum-harness/service-agent.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 101 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,015 The whole file, excluding the scripts and references it only reads on demand.

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	$0.00101	$0.01015
Opus 5.5	$0.00040	$0.00406
Sonnet 5.5	$0.00020	$0.00203
Haiku 4.5	$0.00010	$0.00102

Measured 2mo ago against content hash 437f0c656c54, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

service-agent 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/skills/service-agent/SKILL.md · 132 lines

How it starts

The opening of the file, as written. The whole thing — 132 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Service Agent

You maintain business capability libraries and their service-local distributed semantics.

Responsibility

Own all services/*/ directories — domain service libraries
Maintain domain logic, use cases, policies, port definitions
Maintain services/<name>/model.yaml as the declared index for service-local distributed semantics
Ensure domain logic accesses the external world only through ports
Ensure services are pure libraries (no main.rs, no HTTP server, no consumer loops)
Coordinate with contract-agent when service interfaces change protocol

Read Before Editing

AGENTS.md                                     → global protocol
agent/codemap.yml                             → module constraints (services layer)
.agents/skills/backend-engineering/SKILL.md   → backend quality kernel
platform/model/README.md                      → platform vs service boundary
services/<name>/model.yaml                    → service-local declared semantics index
Individual service Cargo.toml and README.md

Writable Directories

Directory	Scope
`services/**`	Service source code and `model.yaml`
`fixtures/**`	Test data and seed data
`verification/**`	Service-level validation tests
`packages/contracts/**`	When service interfaces change need protocol updates

Forbidden Directories

Directory	Reason
`infra/**`	Owned by platform-ops-agent
`platform/model/**`	Platform-level model owned by platform-ops-agent
`packages//adapters/`	Concrete adapter implementations
`servers/**`	Owned by server-agent
`workers/**`	Owned by worker-agent
Another service's directory	Services must not import each other

Gate Candidates

Select gates from agent/manifests/gate-matrix.yml based on changed paths, risk, and evidence level. Common service signals include:

Gate	Command
Service build check	`cargo check -p <service-package>`
Service tests	`cargo test -p <service-package>`
Typecheck	`just typecheck`
Boundary check	`just boundary-check`

Read the full file on GitHub · 132 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 · 132 lines · 101 tokens per session scan A 437f0c656c54

Subscribe to this mod's changes

service-agent is a skill published in the GitHub repository openclosed-org/axum-harness (51 stars, last pushed 5mo ago), licensed Apache-2.0. It adds 101 tokens to every session and 1,015 once invoked, about $0.0004 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.

Backend and APIs ai-agents axum-framework distributed-systems microservices platform-engineering

service-agent next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
service-agentopenclosed-org/axum-harness	Skill	51	5mo ago	Apache-2.0	A	101	Claude Code, Codex
architecture-paradigm-microservicesathola/claude-night-market	Skill	348	yesterday	MIT	A	33	Claude Code
microservices-expertpersonamanagmentlayer/pcl	Skill	44	11d ago	Apache-2.0	A	52	Claude Code
microservices-patternsbooklib-ai/booklib	Skill	40	7mo ago	MIT	A	131	Claude Code, Codex
distributed-feasibility-checkerbookforge-ai/bookforge-skills	Skill	42	6mo ago	CC-BY-SA-4.0	A	86	Claude Code
api-testing-patternsproffesor-for-testing/agentic-qe	Skill	525	yesterday	MIT	A	34	Claude Code
contract-testingproffesor-for-testing/agentic-qe	Skill	525	yesterday	MIT	A	35	Claude Code

axum-harness: Skill for Claude Code