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.
npx skills add fusengine/agents --skill go-concurrencygit clone --depth 1 https://github.com/fusengine/agentsWrote 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.
[](https://agentmods.dev/skills/fusengine/agents/go-concurrency)<a href="https://agentmods.dev/skills/fusengine/agents/go-concurrency"><img src="https://agentmods.dev/badge/skills/fusengine/agents/go-concurrency/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.
<a href="https://agentmods.dev/skills/fusengine/agents/go-concurrency"><img src="https://agentmods.dev/badge/skills/fusengine/agents/go-concurrency.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00040 | $0.01339 |
| Opus 5.5 | $0.00016 | $0.00536 |
| Sonnet 5.5 | $0.00008 | $0.00268 |
| Haiku 4.5 | $0.00004 | $0.00134 |
Grade A, and why
go-concurrency scanned grade A 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 24d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
g.Go(func() error { return fetch(ctx, u) }) How it starts
The opening of the file, as written. The whole thing — 137 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Go Concurrency
Goroutines, channels, context, and errgroup for Go 1.27 — plus the number-one
documented pitfall: leaking goroutines on an unbuffered channel + early return.
Agent Workflow (MANDATORY)
Before ANY implementation, spawn 3 agents in parallel, one Agent call each with a name:
- fuse-ai-pilot:explore-codebase - Map existing goroutine/channel/context usage
- fuse-ai-pilot:research-expert - Verify errgroup/context docs via Context7/Exa
- mcp__context7__query-docs - Confirm
golang.org/x/sync/errgroupsignatures
After implementation, run fuse-ai-pilot:sniper for validation, and run tests
with go test -race ./....
Overview
| Feature | Description |
|---|---|
| Goroutines & channels | Lightweight concurrency + typed communication |
| errgroup | Parallelism + error aggregation + context cancellation |
| context | First param, propagated strictly, carries cancellation/deadline |
| WaitGroup vs channels | Counting-only vs result/error passing |
| Race detector | -race in tests/CI to catch data races |
| Leak profile (GA 1.27) | pprof.Lookup("goroutineleak") / /debug/pprof/goroutineleak — no GOEXPERIMENT needed |
Critical Rules
context.Contextis the first parameter - namedctx, never stored in a struct- Every started goroutine must be able to exit - or it leaks (see rule 4)
- Prefer
errgroupfor fan-out with errors - it handles wait + first error + cancel - Unbuffered channel + early return = leak - senders block forever; buffer or drain
- Test with
-race- a passing test without-raceproves nothing about races
What ships with it
7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 24d ago Changed · +1 lines 112d65dedc34
- 1mo ago Changed 01974753e24c
- 1mo ago First seen · 136 lines · 40 tokens per session scan A f87f5b0232ad
go-concurrency is a skill published in the GitHub repository fusengine/agents (33 stars, last pushed 9d ago), licensed MIT. It adds 40 tokens to every session and 1,339 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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