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 agentmods add skills/kylepelham/drift/effectnpx skills add kylepelham/Drift --skill effectgit clone --depth 1 https://github.com/kylepelham/DriftWhat 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 | $0.00017 | $0.00586 |
| Opus 5 | $0.00009 | $0.00293 |
| Sonnet 5 | $0.00003 | $0.00117 |
| Haiku 4.5 | $0.00002 | $0.00059 |
Grade A, and why
effect 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 2d 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.
This is a copy
100% identical to effect — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 39 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Effect
This codebase uses Effect for typed, composable TypeScript services, schemas, and workflows.
Source Of Truth
Use the current Effect v4 / effect-smol source, not memory or older Effect v2/v3 examples.
- If
.opencode/references/effect-smolis missing, clonehttps://github.com/Effect-TS/effect-smolthere. Do this in the project, not in the skill folder. - Search
.opencode/references/effect-smolfor exact APIs, examples, tests, and naming patterns before answering or implementing Effect-specific code. - Also inspect existing repo code for local house style before introducing new patterns.
- Prefer answers and implementations backed by specific source files or nearby repo examples.
Guidelines
- Prefer current Effect v4 APIs and project-local patterns over old blog posts, examples, or package-memory guesses.
- Use
Effect.gen(function* () { ... })for multi-step workflows. - Use
Effect.fn("Name")orEffect.fnUntraced(...)for named effects when adding reusable service methods or important workflows. - Prefer Effect
Schemafor API and domain data shapes. Use branded schemas for IDs andSchema.TaggedErrorClassfor typed domain errors when modeling new error surfaces. - Keep HTTP handlers thin: decode input, read request context, call services, and map transport errors. Put business rules in services.
- In Effect service code, prefer Effect-aware platform abstractions and dependencies over ad hoc promises where the surrounding code already does so.
- Keep layer composition explicit. Avoid broad hidden provisioning that makes missing dependencies hard to see.
- In tests, prefer the repo's existing Effect test helpers and live tests for filesystem, git, child process, locks, or timing behavior.
- Do not introduce
any, non-null assertions, unchecked casts, or older Effect APIs just to satisfy types. - Do not answer from memory. Verify against
.opencode/references/effect-smolor nearby code first.
Testing Patterns
- Use
testEffect(...)frompackages/opencode/test/lib/effect.tsfor tests that exercise Effect services, layers, runtime context, scoped resources, or platform integrations. - Use
it.live(...)for filesystem, git repositories, HTTP servers, sockets, child processes, locks, real time, and other live platform behavior. - Run tests from package directories such as
packages/opencode; never run package tests from the repo root. - Prefer explicit test layers over ad hoc managed runtimes. Keep dependency provisioning visible in the test file.
- Use scoped fixtures and finalizers for resources that must be cleaned up, including temporary directories, flags, databases, fibers, servers, and global state.
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.
- 2d ago First seen · 39 lines · 17 tokens per session scan A 0d27f8d40455
effect is a skill published in the GitHub repository kylepelham/Drift (20 stars, last pushed 2d ago), licensed MIT. It adds 17 tokens to every session and 586 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to effect, differing in 0 lines, and is treated as a copy.
Other skills, from other repositories
qa-testing
Verify your work by actually operating the app or website you changed, instead of assuming it works. Strongly recommended whenever you build, modify, or debug a web app, website, or desktop GUI app. Drive real browsers with the agent-browser CLI and native desktop apps with the cua-driver CLI. These are installed on…
best-of-n
Generate a small set of independent candidate solutions in worktrees, judge them against one explicit rubric, and apply the winner only after PASS verification.
contributor-onboarding
Help a new contributor get productive on this checkout - inspect sync state against main, build, run the repository's exact verification gate, and produce a local what's-new digest. Never fetches, pulls, or modifies a dirty tree on its own. Explicit-only.
fleet-manager
Use when managing, triaging, restarting, escalating, or summarizing Codewhale Agent Fleet runs and workers.
handoff
Write a compact, decision-ready handoff so the next session (or the user) can continue without reconstructing the current one. Use when the session is ending, context is running low, the user asks for a handoff / "pass the baton" / "hand off", or a long-running operation needs a durable state checkpoint.
codew-release-qa-sweep
Use before claiming CodeWhale release work is done: run the full gate sweep and list the manual QA targets.