Claude Code Skills Marketplace is a collection and marketplace of skills, plugins, agents, and instructions that extend Claude Code with specialized development workflows. It is for developers who want to install existing workflows or create, validate, and package their own Claude Code skills.
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 skills/daymade/claude-code-skills/codex-1m-context-window-setupnpx skills add daymade/claude-code-skills --skill codex-1m-context-window-setupgit clone --depth 1 https://github.com/daymade/claude-code-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/daymade/claude-code-skills/codex-1m-context-window-setup)<a href="https://agentmods.dev/skills/daymade/claude-code-skills/codex-1m-context-window-setup"><img src="https://agentmods.dev/badge/skills/daymade/claude-code-skills/codex-1m-context-window-setup.svg" alt="Measured on agentmods" 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 | $0.00151 | $0.01141 |
| Opus 5 | $0.00076 | $0.00571 |
| Sonnet 5 | $0.00030 | $0.00228 |
| Haiku 4.5 | $0.00015 | $0.00114 |
Grade A, and why
codex-1m-context-window-setup 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 5d 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 — 124 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Codex 1m Context Window Setup
Expand future Codex sessions without pretending every model supports one million tokens. The bundled script reads Codex's current model catalog, caps the request at the selected model's declared maximum, and applies the user's established 60% auto-compaction policy.
Route the request
| User intent | Action |
|---|---|
| Inspect the current limit, explain 258K, or preview the recommendation | Run doctor |
| Configure/fix/raise the context window | Run apply |
| Confirm a prior setup is still correct after an update or model switch | Run verify |
Do not ask the user for raw token numbers. The model catalog is the authority and the script derives the attainable values.
Run the workflow
When this Skill loads, the host exposes its installed path. Resolve it explicitly:
- In Codex, take the directory containing
SKILL.mdfrom this Skill'sfile:entry in the current Available skills catalog. - In Claude Code, use the Base directory for this skill shown by the Skill load result.
Do not search a home directory for another copy. If the host did not expose an
installed path, stop with installed Skill path not exposed rather than guessing.
On macOS/Linux, set that exact directory and run:
SKILL_DIR="/absolute/path/from-the-loaded-skill-metadata"
uv run --no-project python "$SKILL_DIR/scripts/codex_context_window.py" doctor
uv run --no-project python "$SKILL_DIR/scripts/codex_context_window.py" apply
uv run --no-project python "$SKILL_DIR/scripts/codex_context_window.py" verify
On Windows PowerShell, use the same exposed directory with forward slashes:
$SkillDir = "C:/absolute/path/from-the-loaded-skill-metadata"
uv run --no-project python "$SkillDir/scripts/codex_context_window.py" doctor
uv run --no-project python "$SkillDir/scripts/codex_context_window.py" apply
uv run --no-project python "$SkillDir/scripts/codex_context_window.py" verify
doctor
Run first. It is read-only and reports:
What ships with it
4 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.
- 5d ago First seen · 124 lines · 151 tokens per session scan A cbbef49eded2
codex-1m-context-window-setup is a skill published in the GitHub repository daymade/claude-code-skills (1,375 stars, last pushed yesterday), licensed MIT. It adds 151 tokens to every session and 1,141 once invoked, about $0.0008 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.
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