phase-gate

phase-gate is a skill for Claude Code from SteveGJones/ai-first-sdlc-practices. It costs 39 tokens per session (680 once invoked), scanned A, original, MIT.

A validator for software-project phases: requirements, design, testing, and code. It checks that expected documents exist and that references between phases are valid.

In plain words
What is it for?
It helps enforce phase gates for features documented under docs/specs/, including checks against selected source files.
Why use it?
It catches missing planning or test material and broken links between project stages before work can proceed.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter. Also seen: positional $N argument.

Part of the sdlc-programme plugin — 5 skills shipped together

Good fit It helps enforce phase gates for features documented under docs/specs/, including checks against selected source files.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/stevegjones/ai-first-sdlc-practices/phase-gate
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 SteveGJones/ai-first-sdlc-practices --skill phase-gate
Clone the repo
git clone --depth 1 https://github.com/SteveGJones/ai-first-sdlc-practices

Made for: Claude Code.

Or install sdlc-programme, the plugin that ships this one along with the rest of its 5 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 phase-gate

README.md
[![agentmods](https://agentmods.dev/badge/skills/stevegjones/ai-first-sdlc-practices/phase-gate/github.svg)](https://agentmods.dev/skills/stevegjones/ai-first-sdlc-practices/phase-gate)
Your own site
<a href="https://agentmods.dev/skills/stevegjones/ai-first-sdlc-practices/phase-gate"><img src="https://agentmods.dev/badge/skills/stevegjones/ai-first-sdlc-practices/phase-gate/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-gate

Your own site · 80×15
<a href="https://agentmods.dev/skills/stevegjones/ai-first-sdlc-practices/phase-gate"><img src="https://agentmods.dev/badge/skills/stevegjones/ai-first-sdlc-practices/phase-gate.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 39 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 680 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00039 $0.00680
Opus 5.5 $0.00016 $0.00272
Sonnet 5.5 $0.00008 $0.00136
Haiku 4.5 $0.00004 $0.00068

Measured 1mo ago against content hash 0c5fd48a5164, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

phase-gate 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 1mo 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.

plugins/sdlc-programme/skills/phase-gate/SKILL.md · 94 lines

How it starts

The opening of the file, as written. The whole thing — 94 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Run a Phase Gate

Run the named gate validator against a feature's phase artefacts.

Arguments

  • <phase> — one of requirements, design, test, code
  • <feature-id> — short slug for the feature
  • [code-file-glob] — only required when <phase> is code; e.g., src/**/*.py

Steps

PHASE="$1"
FEATURE_ID="$2"
CODE_GLOB="${3:-}"

if [ -z "$PHASE" ] || [ -z "$FEATURE_ID" ]; then
    echo "Usage: phase-gate <phase> <feature-id> [code-file-glob]" >&2
    exit 1
fi

case "$PHASE" in
    requirements|design|test|code) ;;
    *)
        echo "phase must be one of: requirements, design, test, code" >&2
        exit 1
        ;;
esac

FEATURE_DIR="docs/specs/$FEATURE_ID"

if [ "$PHASE" = "code" ] && [ -z "$CODE_GLOB" ]; then
    echo "code phase requires a code-file-glob (e.g., 'src/**/*.py')" >&2
    exit 1
fi

python3 << PYEOF
from pathlib import Path
from sdlc_programme_scripts.programme.gates import (
    code_gate, design_gate, requirements_gate, test_gate,
)

phase = "$PHASE"
feature_id = "$FEATURE_ID"
feature_dir = Path("$FEATURE_DIR")

if phase == "requirements":
    result = requirements_gate(feature_dir, feature_id)
elif phase == "design":
    result = design_gate(feature_dir, feature_id)
elif phase == "test":
    result = test_gate(feature_dir, feature_id)
elif phase == "code":
    code_glob = "$CODE_GLOB"
    code_text = ""
    for path in Path().glob(code_glob):
        if path.is_file():
            code_text += path.read_text() + "\n"
    result = code_gate(feature_dir, feature_id, code_text=code_text)

if result.passed:
    print(f"PASS: {result.gate_name}-gate for feature {result.feature_id}")
    raise SystemExit(0)
else:
    print(f"FAIL: {result.gate_name}-gate for feature {result.feature_id}")
    for err in result.errors:
        print(f"  - {err}")
    raise SystemExit(1)
PYEOF

Done

Report:

  • Gate name and feature-id
  • PASS or FAIL
  • For FAIL: each broken reference / missing artefact

Read the full file on GitHub · 94 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. 1mo ago First seen · 94 lines · 39 tokens per session scan A 0c5fd48a5164

Subscribe to this mod's changes

phase-gate is a skill published in the GitHub repository SteveGJones/ai-first-sdlc-practices (41 stars, last pushed 15d ago), licensed MIT. It adds 39 tokens to every session and 680 once invoked, about $0.0002 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 2026-09-03.

Related

Other skills, from other repositories

research-engineer

An uncompromising Academic Research Engineer. Operates with absolute scientific rigor, objective criticism, and zero flair. Focuses on theoretical correctness, formal verification, and optimal implementation across any required technology.

davila7/claude-code-templates · 43 tokens

eval-dataset-design

A guide to creating reliable test sets for AI agents. Each evaluation task includes the request, the simulated user's behaviour, a reset starting state, and a success check that can be independently verified.

bojieli/ai-agent-book · 138 tokens

tika-eval-compare

Compare extracts from two Tika builds over a corpus to detect regressions in content, encoding, exceptions, and embedded-document handling. Use for "compare before/after extracts", "eval this change against the corpus".

apache/tika · 50 tokens

cua-driver

Use Cua Driver for desktop or browser tasks that are awkward or unavailable through Bash/APIs, or when the user explicitly wants GUI interaction: app testing, visual bug reproduction, form filling, calendar entry, screenshots, and demo recording. Also covers Cua setup; not OpenAI Codex Computer Use or web research.

davidondrej/skills · 68 tokens

jetson-validate-image

Use after jetson-flash-image to run static BSP checks, on-target smoke/regression tests on a flashed DUT, or both. Not for build or flash steps. Triggers: validate bsp, on-target validation.

NVIDIA/skills · 50 tokens

atmos-validation

Validate Atmos projects, components, arbitrary JSON Schema inputs, EditorConfig, and GitHub Actions; use affected-file selection and native CI annotations.

cloudposse/atmos · 31 tokens