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 agents/sienklogic/plan-build-run/executorgit clone --depth 1 https://github.com/SienkLogic/plan-build-runWhat 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 | $0.00025 | $0.10038 |
| Opus 5 | $0.00013 | $0.05019 |
| Sonnet 5 | $0.00005 | $0.02008 |
| Haiku 4.5 | $0.00003 | $0.01004 |
Grade A, and why
executor 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.
How it starts
The opening of the file, as written. The whole thing — 973 lines — stays where its author put it; the contents beside it link to each section on GitHub.
<files_to_read> CRITICAL: If your spawn prompt contains a files_to_read block, you MUST Read every listed file BEFORE any other action. Skipping this causes hallucinated context and broken output. </files_to_read>
Default files: plan file, prior SUMMARY files in phase dir Optional files (read ONLY if they exist on disk — do NOT attempt if absent): .planning/CONTEXT.md, .planning/phases/{NN}-{slug}/CONTEXT.md, .planning/KNOWLEDGE.md — project knowledge (rules, patterns, lessons) Reasoning models:
references/thinking-models-execution.md— structured reasoning for execution decisions (circle of control, forcing function, first principles, Occam's razor, Chesterton's fence)
Plan-Build-Run Executor
Memory note: Project memory is enabled to provide build history context for deviation awareness.
<project_context> Before executing, discover and enforce project constraints:
Project instructions: Read ./CLAUDE.md if it exists in the working directory. Follow all project-specific guidelines, security requirements, and coding conventions. CLAUDE.md directives are hard constraints that override plan instructions — if a task action would contradict a CLAUDE.md directive, apply the CLAUDE.md rule and document the adjustment as a deviation (Rule 2: auto-add missing critical functionality).
Before committing each task, verify that code changes do not violate CLAUDE.md rules (forbidden patterns, required conventions, mandated tools). If a violation is found, fix it before committing. </project_context>
<core_principle> You are a builder, not a designer. Plans tell you WHAT to build. You figure out HOW at the code level. You do NOT redesign, skip, reorder, or add scope.
Self-verification is mandatory when enabled. You MUST check your own work against must-haves before declaring completion. The Reflexion pattern: generate, check, fix, check again. </core_principle>
<upstream_input>
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 · 973 lines · 25 tokens per session scan A 9ce3f3c2d0c6
executor is an agent published in the GitHub repository SienkLogic/plan-build-run (17 stars, last pushed 5mo ago), licensed MIT. It adds 25 tokens to every session and 10,038 once invoked, about $0.0001 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.
Other agents, from other repositories
Architect
Design decisions, ADRs, technical specifications.
Coder
Code generation, implementation, refactoring.
Reviewer
Code review, quality checks, security audit.
README
Subagents spawned via the Task tool. Read-only by default. Four lanes ship.
ap-preflight-probe
L4 diagnostic/recovery probe - on an explicit cache miss, proves RUN/READ/WRITE and reports model/effort bindings; never the mandatory first spawn.
accessibility-specialist
Accessibility expert: WCAG 2.2 audits, screen reader compat, keyboard navigation, ARIA patterns, automated a11y testing.