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 OutlineDriven/outline-driven-development --skill fastoptgit clone --depth 1 https://github.com/OutlineDriven/outline-driven-developmentWrote 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/outlinedriven/outline-driven-development/fastopt)<a href="https://agentmods.dev/skills/outlinedriven/outline-driven-development/fastopt"><img src="https://agentmods.dev/badge/skills/outlinedriven/outline-driven-development/fastopt.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00049 | $0.00702 |
| Opus 5 | $0.00024 | $0.00351 |
| Sonnet 5 | $0.00010 | $0.00140 |
| Haiku 4.5 | $0.00005 | $0.00070 |
Grade A, and why
fastopt 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- fastopt — 100% identical, 0 lines differ
How it starts
The opening of the file, as written. The whole thing — 40 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Fastopt
Contract
| Field | Bound contract |
|---|---|
| Trigger | User wants to optimize suspected hot paths without waiting for benchmarks, labeling claims as hypotheses. |
| Authority | Read-only. No file, VCS, credential, paid, published, deployed, or remote mutation. |
| Side effect | Chat output only: hypotheses and benchmark designs before any mutation or performance claim. |
| Done | Hypotheses and benchmark designs for suspected hot paths are emitted; no mutation or speed claim made. |
Inputs
Required: one or more suspected hot paths named by the user (file, function, or call site) and the workload or input shape that makes each path hot.
Optional: prior measurements, profiling traces, or environment constraints the user supplies. Absent measurements are treated as unmeasured, not as evidence of slowness.
Procedure
- For each named hot path, read the source and surrounding call graph read-only; record the inputs, allocations, loops, and branches that plausibly dominate cost. Done when: every named path is read and its cost-plausible elements recorded.
- Label every cost observation a hypothesis, not a finding: state the assumed workload, the assumed dominant operation, and the assumed magnitude rank, with no speed claim. Done when: every observation carries its hypothesis label with workload, dominant operation, and magnitude rank.
- For each hypothesis, design a benchmark that would confirm or refute it: name the metric, the baseline, the variant, the workload generator, the warm-up, the repetition count, and the noise controls. Done when: every hypothesis has a benchmark design with all seven elements named.
- Bound the change scope implied by each hypothesis to the named path; do not propose edits outside it or assume a fix is correct. Done when: every hypothesis's implied change scope is bounded to its named path.
- If a hypothesis cannot be tested without mutating code, state the minimal mutation needed to measure it and stop before performing it. Done when: the blocking reason and minimal mutation are stated, or the hypothesis is testable read-only.
- Emit the hypotheses and benchmark designs as chat output. Make no mutation and no speed claim. Done when: the chat report is emitted with no mutation and no speed claim.
What ships with it
1 file 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.
- 2d ago First seen · 40 lines · 49 tokens per session scan A d65364c19f3b
fastopt is a skill published in the GitHub repository OutlineDriven/outline-driven-development (52 stars, last pushed today), licensed Apache-2.0. It adds 49 tokens to every session and 702 once invoked, about $0.0002 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 2026-09-03.
Other skills, from other repositories
audit-project
Run an iterative multi-agent code audit until critical and high findings are resolved. Use when the user says "audit my code", "find all the bugs", "deep code audit", "iterative review", or "review until clean".
optimize
Use when asked to optimize code, speed up a path, reduce allocations, repair a regression, or profile a target. Not for remote, credential, publish, deploy, or irreversible changes.
debug
Hypothesis-driven debugging. Use when a test fails, a crash or exception occurs, output is wrong, or an intermittent flake has no obvious cause.
ios-build-fix
Use when asked to run /ios-build-fix to fix a failing iOS build, regenerate an Xcode project from project.yml, or correct UI behavior. Not for a clean rebuild: use ios-build-cleanup.
extremely-optimize
Use when asked to run a performance campaign against a measured floor. Not for hypothesis-only analysis without mutation: use fastopt.
ast-grep
Use when asked to run AST-based structural search, lint, or rewrite of code when regex is too fragile. Not for remote, credential, publish, deploy, or irreversible changes.