slicing-into-tracer-bullets

slicing-into-tracer-bullets is a skill for Claude Code from smixs/disruptor-skills. It costs 77 tokens per session (1,142 once invoked), scanned A, original, MIT.

A planning method for breaking a large software project into small, end-to-end pieces called tracer bullets. Each piece crosses the layers it needs, such as data storage, server code, interface, and tests.

In plain words
What is it for?
Use it to turn a finished feature specification into ordered development tasks, with boundaries, acceptance checks, and stated dependencies.
Why use it?
It avoids building one technical layer at a time without producing something usable. Each slice can be built, tested, and demonstrated on its own, making the build order clearer.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the disruptor plugin — 12 skills shipped together

Good fit Use it to turn a finished feature specification into ordered development tasks, with boundaries, acceptance checks, and stated dependencies.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/smixs/disruptor-skills/slicing-into-tracer-bullets
Install

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.

Any agent
npx skills add smixs/disruptor-skills --skill slicing-into-tracer-bullets
Clone the repo
git clone --depth 1 https://github.com/smixs/disruptor-skills

Made for: Claude Code.

Or install disruptor, the plugin that ships this one along with the rest of its 12 skills.

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.

agentmods badge for slicing-into-tracer-bullets

README.md
[![agentmods](https://agentmods.dev/badge/skills/smixs/disruptor-skills/slicing-into-tracer-bullets/github.svg)](https://agentmods.dev/skills/smixs/disruptor-skills/slicing-into-tracer-bullets)
Your own site
<a href="https://agentmods.dev/skills/smixs/disruptor-skills/slicing-into-tracer-bullets"><img src="https://agentmods.dev/badge/skills/smixs/disruptor-skills/slicing-into-tracer-bullets/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.

agentmods 80×15 button for slicing-into-tracer-bullets

Your own site · 80×15
<a href="https://agentmods.dev/skills/smixs/disruptor-skills/slicing-into-tracer-bullets"><img src="https://agentmods.dev/badge/skills/smixs/disruptor-skills/slicing-into-tracer-bullets.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 77 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,142 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00077 $0.01142
Opus 5 $0.00039 $0.00571
Sonnet 5 $0.00015 $0.00228
Haiku 4.5 $0.00008 $0.00114

Measured 12d ago against content hash 3f0d7c7069ea, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

slicing-into-tracer-bullets 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 12d 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.

skills/slicing-into-tracer-bullets/SKILL.md · 89 lines

How it starts

The opening of the file, as written. The whole thing — 89 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Slicing into tracer bullets

Stage contract

  • Stage: 4. Breakdown · Kind: method
  • Inputs: the canonical spec (stage 2) + the module boundaries (stage 3).
  • Outputs: an ordered list of vertical slices, each with acceptance criteria, scope boundaries, and Blocked by: links — one slice = one build-loop run.
  • Entry gate: the spec is build-ready and it is bigger than one slice. A single-slice job skips this stage — build it directly.
  • Done when: every slice is end-to-end (touches all layers it needs), demoable/verifiable alone, and its dependencies are stated. No horizontal-only ("schema-only", "API-only") items remain.
  • Next: two engines. Sequential (default): the converging-and-polishing skill — run the build loop once per slice, each in its own fresh session seeded from the spec + that one slice. Fleet (gate G3F: parallelizable across independent nodes AND budget for a worker fleet): the delivering-mvp-fleet skill — it builds its own board from the spec + slices.
  • Maintains:

Why vertical, not horizontal

A tracer bullet is a thin slice that cuts through all the layers it touches — schema, backend, adapter, UI, tests — and delivers one small end-to-end behavior that you can actually run and see. It is the opposite of a horizontal layer ("build the whole DB schema", then "build the whole API"), which produces nothing demoable until the last layer lands and hides integration risk until the end.

Why it matters for an agent build: each vertical slice is small enough to build, review, and converge in one focused session without the context filling up. The integration seams — the places things actually break — get exercised on slice #1, not discovered at the end. And each slice merges independently.

What makes a good slice

  • End-to-end. It reaches every layer its behavior needs. If a slice can't be demoed or verified without a future slice, it isn't a slice yet — it's a layer.
  • Demoable / verifiable alone. There's a concrete way to see it work: a request that returns the right thing, a screen that renders, a test that passes.
  • Small. Sized to one build-loop run. If it won't converge in one session, split it.
  • Scoped. State what it explicitly does NOT cover (goes to a later slice), so the builder doesn't gold-plate.
  • Behavioral, not procedural. Describe what the slice must do (interfaces, contracts, acceptance criteria) — not how to code it, and not by pointing at file paths/line numbers that will have drifted by the time it's built.

Read the full file on GitHub · 89 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.

  1. 12d ago First seen · 89 lines · 77 tokens per session scan A 3f0d7c7069ea

Subscribe to this mod's changes

slicing-into-tracer-bullets is a skill published in the GitHub repository smixs/disruptor-skills (18 stars, last pushed 2mo ago), licensed MIT. It adds 77 tokens to every session and 1,142 once invoked, about $0.0004 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 2026-08-30.

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