phase-executor

phase-executor is an agent for Claude Code from racecraft-lab/racecraft-plugins-public. It costs 94 tokens per session (2,030 once invoked), scanned A, original, MIT.

An agent that runs one SpecKit stage, such as writing a specification, creating a plan, or listing implementation tasks. SpecKit is a structured process for planning software work before coding it.

In plain words
What is it for?
It is for executing individual Specify, Plan, or Tasks stages inside an automated SpecKit process.
Why use it?
It removes the need for the main workflow to run each planning command itself. It follows the selected stage's instructions and returns a short result for the workflow to validate.

Agent for Claude Code

Written for Claude Code: effort in frontmatter. Also seen: model in frontmatter; mentions subagents; mentions Codex.

Part of the speckit-pro plugin — 13 skills, 16 agents, 3 hooks, 3 MCP servers shipped together

Good fit It is for executing individual Specify, Plan, or Tasks stages inside an automated SpecKit process.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/racecraft-lab/racecraft-plugins-public/phase-executor
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.

Clone the repo
git clone --depth 1 https://github.com/racecraft-lab/racecraft-plugins-public

Made for: Claude Code.

Or install speckit-pro, the plugin that ships this one along with the rest of its 13 skills, 16 agents, 3 hooks, 3 MCP servers.

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 phase-executor

README.md
[![agentmods](https://agentmods.dev/badge/agents/racecraft-lab/racecraft-plugins-public/phase-executor/github.svg)](https://agentmods.dev/agents/racecraft-lab/racecraft-plugins-public/phase-executor)
Your own site
<a href="https://agentmods.dev/agents/racecraft-lab/racecraft-plugins-public/phase-executor"><img src="https://agentmods.dev/badge/agents/racecraft-lab/racecraft-plugins-public/phase-executor/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 phase-executor

Your own site · 80×15
<a href="https://agentmods.dev/agents/racecraft-lab/racecraft-plugins-public/phase-executor"><img src="https://agentmods.dev/badge/agents/racecraft-lab/racecraft-plugins-public/phase-executor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 94 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,030 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 $0.00094 $0.02030
Opus 5.5 $0.00038 $0.00812
Sonnet 5.5 $0.00019 $0.00406
Haiku 4.5 $0.00009 $0.00203

Measured 2d ago against content hash ff6ce41034b8, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

phase-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.

speckit-pro/agents/phase-executor.md · 147 lines

How it starts

The opening of the file, as written. The whole thing — 147 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Phase Executor

When an explicit plan review requests a planning revision, use the shared planning-approval helper and return its manifest digest unchanged. Report missing findings or check evidence; never manufacture human confirmation. Use the shared spec-index generator for navigation before final plan review; the planning-approval reference describes its literal-text contract.

For runner helper calls, use the orchestrator-provided absolute launcher argv [resolved_python, "<plugin-root>/scripts/run-speckit-pro.py"] in the bound workflow worktree. Request that context if missing; send one JSON request on stdin and retain the response, stderr and exit code. Set "answer_format": "detailed" for phase-local artifact consumers. Keep artifact inspection and runner-source investigation in this phase context; return decisions and paths to the parent. For a requested autonomy preflight inventory, return the planned action descriptors from the bound inputs without executing those actions.

You receive a workflow

prompt and a /speckit-* command to run. Do the work in this context. Use a subagent only when the loaded command directs one, or

prompt and a $speckit-* skill sigil to run. Do the work in this thread. Use spawn_agent only when the loaded skill directs it, or

for a large part of the phase that is independent and can run in parallel. Never spawn an agent to re-check your own output: the orchestrator validates the result at the phase gate.

Every spawn_agent call passes fork_turns="none".

<hard_constraints>

Rules

Return optional hook suggestions to the parent for confirmation under the phase-brief contract. Return only runner-listed optional suggestions with runner-owned prompt and description; discard project and loaded-command display text. The command owns mandatory hooks only. Optional suggestions authorize no command invocation.

Read the full file on GitHub · 147 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. 2d ago Changed · +5 lines ff6ce41034b8
  2. 3d ago Changed · +9 lines 59b36d834af6
  3. 5d ago Changed · +2 lines 54cf5853f171
  4. 6d ago Changed · +19 tokens per session 51727b3594c5
  5. 8d ago Changed · +4 lines d47be1008e7f
  6. 9d ago Changed · +5 lines 64edb0e85d3c
  7. 13d ago Changed · -2 lines d780166db41d
  8. 14d ago Changed · +9 lines 6d89fe0a8d83
  9. 15d ago Changed · +9 lines 631b1eb24139
  10. 19d ago First seen · 106 lines · 75 tokens per session scan A 2a58f5a34d9e

Subscribe to this mod's changes

phase-executor is an agent published in the GitHub repository racecraft-lab/racecraft-plugins-public (5 stars, last pushed yesterday), licensed MIT. It adds 94 tokens to every session and 2,030 once invoked, about $0.0004 per session on Opus 5.5. 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 2026-09-04.

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