context-engineering-planner

context-engineering-planner is a skill for Claude Code, Codex from 45ck/skill-harness. It costs 30 tokens per session (271 once invoked), scanned A, original, MIT.

A planning guide for deciding what information an agent needs during a workflow or long task. It separates lasting project sources, temporary work notes, test evidence, and reusable memory.

In plain words
What is it for?
Use it to plan an agent's source files, issue context, tests, logs, retrieval rules, summaries, memory, and refresh checks.
Why use it?
It prevents agents from relying on one large, confusing prompt or stale recollections. It makes clear what to retrieve, summarize, store, or leave out.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/45ck/skill-harness/context-engineering-planner
Any agent
npx skills add 45ck/skill-harness --skill context-engineering-planner
Clone the repo
git clone --depth 1 https://github.com/45ck/skill-harness

Made for: Claude Code, Codex.

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 context-engineering-planner

README.md
[![agentmods](https://agentmods.dev/badge/skills/45ck/skill-harness/context-engineering-planner.svg)](https://agentmods.dev/skills/45ck/skill-harness/context-engineering-planner)
Your own site
<a href="https://agentmods.dev/skills/45ck/skill-harness/context-engineering-planner"><img src="https://agentmods.dev/badge/skills/45ck/skill-harness/context-engineering-planner.svg" alt="Measured on agentmods" height="20"></a>
Per session 30 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 271 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00030 $0.00271
Opus 5 $0.00015 $0.00135
Sonnet 5 $0.00006 $0.00054
Haiku 4.5 $0.00003 $0.00027

Measured 4d ago against content hash e5f6eabccd72, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

context-engineering-planner 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 4d 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.

packs/agent-operating-skills/skills/context-engineering-planner/SKILL.md · 37 lines

What it actually says

Context Engineering Planner

Use this skill when an agent workflow needs deliberate context design instead of a large undifferentiated prompt.

Plan

  • Identify the decision the agent must make and the evidence it needs.
  • Split context into durable source, transient working context, generated evidence, and memory candidates.
  • Prefer repo files, issues, manifests, tests, traces, and docs over prose recollection.
  • Define what may be retrieved automatically and what must be explicitly requested.
  • Define what should be compressed, summarized, or excluded.
  • Name stale-context risks and refresh checks.

Context Classes

  • source: canonical specs, code, issues, policies, manifests
  • evidence: tests, logs, screenshots, traces, evaluation results
  • memory: reusable lessons worth recording with the project memory mechanism
  • working: temporary notes used only for the current run
  • excluded: secrets, private data, raw traces, irrelevant history, stale generated output

Output

Workflow Goal

Required Source Context

Evidence Inputs

Retrieval Plan

Compression Plan

Memory Candidates

Exclusions

Refresh Checks

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. 4d ago First seen · 37 lines · 30 tokens per session scan A e5f6eabccd72

Subscribe to this mod's changes

context-engineering-planner is a skill published in the GitHub repository 45ck/skill-harness (15 stars, last pushed 2mo ago), licensed MIT. It adds 30 tokens to every session and 271 once invoked, about $0.0002 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.

Related

Other skills, from other repositories

qmd

Search the vault using QMD semantic search. Use PROACTIVELY before reading files. Preference order: (1) MCP tools — mcpqmdquery, mcpqmdget, mcpqmdmultiget, mcpqmdstatus — if they appear in your tool menu, use them first; (2) CLI qmd --index ... as fallback; (3) Grep/Glob only when QMD is not installed. Trigger…

breferrari/obsidian-mind · 142 tokens

sessions

Search and ask questions about coding agent session history across Claude Code, Codex, and Cursor. Use when asking what was worked on, what was tried before, how a problem was investigated across sessions, what happened recently, or any question about past agent sessions. Also use when the user references prior…

slopus/happy · 78 tokens

handover

Use when wrapping up or capturing the current state of a coding session — writes a short, dated entry to the repo's RepoHandover.md so a future agent or you can resume without grepping archived sessions. Triggers on "handover", "hand off", "write handover", "capture state", "checkpoint this session".

jazzyalex/agent-sessions · 71 tokens

map-debug

Structured MAP debugging via task-decomposer, actor, and monitor agents. Use when reproducing a bug, isolating a regression, or diagnosing an error with specialized agents — including failing or flaky tests (pytest AssertionError), crashes and segmentation faults, memory-corruption or memory errors in native/C…

azalio/map-framework · 213 tokens

map-memory-now

Finalize cross-session memory on demand; --finalize-all sweeps every dirty scratch. Use when ending a long session or before switching branches. Do NOT use for routine edits — finalize auto-runs at next SessionStart. Requires claude + git.

azalio/map-framework · 54 tokens

marm-init

Guided MARM MCP setup. Invoke after running marm-memory init on the CLI to configure MARM memory across your agent. Drives transport choice, runtime choice, MCP config writing, multi-agent linking, and server start. Works on Claude, Codex, Gemini, Qwen, Cursor, VS Code, and other MCP-capable agents.

Lyellr88/marm-memory · 75 tokens