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 EthanSei/skills --skill deep-plangit clone --depth 1 https://github.com/EthanSei/skillsWrote 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/ethansei/skills/deep-plan)<a href="https://agentmods.dev/skills/ethansei/skills/deep-plan"><img src="https://agentmods.dev/badge/skills/ethansei/skills/deep-plan/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.
<a href="https://agentmods.dev/skills/ethansei/skills/deep-plan"><img src="https://agentmods.dev/badge/skills/ethansei/skills/deep-plan.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00098 | $0.03108 |
| Opus 5.5 | $0.00039 | $0.01243 |
| Sonnet 5.5 | $0.00020 | $0.00622 |
| Haiku 4.5 | $0.00010 | $0.00311 |
Grade A, and why
deep-plan 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 2mo 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 — 301 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Deep Plan
Multi-perspective architecture planning. Spawns specialist agents for different quality-attribute concerns that evaluate trade-offs before you write code.
When This Skill Activates
Trigger on architecture and planning requests:
- User says: "plan", "architect", "design", "how should I architect..."
- User asks: "deep plan", "plan the architecture", "technical design"
- User wants pre-implementation architecture evaluation
Do NOT activate on every task. This is for deliberate architecture planning, not quick feature additions. Simple features don't need a 6-agent swarm.
Phase 1: Context Gathering
Before spawning agents, establish scope:
- Check for deep-research artifact: Scan recent conversation context for the
structured JSON artifact from deep-research (contains task, tech_stack, approaches,
findings, verdict). Validate the artifact has at minimum:
task,tech_stack, and at least one approach with a summary. If any required field is missing or empty, treat as if no artifact was found and fall through to step 2. If valid, use it as primary input — skip step 2 and use the recommended approach as the starting architecture to evaluate. - If no artifact: Gather context manually:
- Run
git rev-parse --show-toplevelfor{repo_root} - Check for package manifests to identify
{tech_stack}. If no manifests are found, infer tech_stack from primary file extensions (.py,.ts,.go, etc.) or ask the user. Never pass an empty tech_stack to planning agents. - Ask the user what they're building and what constraints matter most
- Read existing code in the affected area to understand current architecture
- Run
- speak-memory: If
.speak-memory/index.mdexists and an active story matches, read it for context. Skip if.speak-memory/does not exist. - Frame the architecture: State what is being planned:
- Feature/System: What is being designed
- Scope: Which components, modules, or layers are affected
- Constraints: Performance targets, security requirements, compatibility needs
- Starting approach: From deep-research artifact, or from user description
- Set scope budget: "Budget: 5 planning specialists + 1 trade-off arbiter = 6 agent calls." Present to user:
What ships with it
3 files 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.
- 2mo ago First seen · 301 lines · 98 tokens per session scan A 4b8a29fca8b8
deep-plan is a skill published in the GitHub repository EthanSei/skills (2 stars, last pushed 8mo ago), licensed MIT. It adds 98 tokens to every session and 3,108 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 2026-08-31.
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