Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents; keep summaries in the main thread, not raw payloads.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Guard the Context Window
**Why:** Context overflow degrades reasoning quality, creates compression artifacts, and halts progress.
**Pattern:**
- **Size phases and cap scope.** Limit files per phase, set turn budgets, account for mechanism costs.
The line at the top of this page pins the label git:20261012.0cb79b5, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
A 17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.
pass: Frontmatter block present
pass: Frontmatter declares a name
pass: Frontmatter declares a description
pass: Size between 200 bytes and 200 KB (488 bytes)
pass: No zero-width or bidi control characters
pass: No instruction hidden inside an HTML comment
pass: No link to an exfiltration or paste host
pass: No credential-shaped string
pass: No instruction to send local credentials anywhere
pass: No text hidden with inline styles
pass: No prompt-injection phrasing
pass: No curl or wget piped into a shell
pass: No recursive delete of root, home or parent
pass: No instruction to read or print local credentials
pass: No base64 blob over 200 characters
pass: No link to a raw IP address
pass: No script tag
Source
GitHub
creedants/pstack-t3 · 15 stars · license MIT · pushed 2026-10-19 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_bgu7a4w4ign5vo43
GET https://markdownregistry.com/api/v1/resolve?ref=creedants/pstack-t3/principle-guard-the-context-window
GET https://markdownregistry.com/api/v1/blob/478752e80498d65c173f52c95db65322bbc98fb31139e406e160e54a5a11aa2b
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
creedants/pstack-t3 · skills/architect/SKILL.md · Sketch types, signatures, and module structure before code, then stay in the loop while implementation fills in. Use…
creedants/pstack-t3 · skills/arena/SKILL.md · Spawn N parallel candidates at the same task, pick a base, graft the strongest parts of the losers into it. Use for…
creedants/pstack-t3 · skills/automate-me/SKILL.md · Use for "automate me", "create/update/refresh my -mode skill", "turn/capture my preferences or working style into a…
creedants/pstack-t3 · skills/benchmark-checklist/SKILL.md · Vet a perf measurement (limiter, tuning, limits, errors, repeatability, relevance, and whether the work happened)…
creedants/pstack-t3 · skills/blast-radius/SKILL.md · Find what a change could break somewhere else before it ships, beyond the diff, and prove the one fact it's safe…
creedants/pstack-t3 · skills/brigade-admin/SKILL.md · Run the executive admin for the brigade coordinators on one repository. It is one pinned T3 thread that forwards the…
creedants/pstack-t3 · skills/brigade/SKILL.md · Give a project or a focus area its own standing head chef. It is one long-lived T3 thread that holds a purpose, takes…
creedants/pstack-t3 · skills/correct/SKILL.md · Find the mistakes agents keep repeating in this repo and make each one impossible. Try architecture first, then types…
creedants/pstack-t3 · skills/create-formal-verification-skill/SKILL.md · Generate a project-local skill that formally verifies the code where a bug costs the most and tests reach the least, in…
creedants/pstack-t3 · skills/create-verification-skill/SKILL.md · Generate a project-local verification skill that drives your app the way a user does — any language, framework, or…
cursor/plugins · harness/pstack/claude-code/skills/principle-guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
cursor/plugins · pstack/skills/principle-guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
michael-denyer/pstack-claude · plugins/pstack/skills/principle-guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
backnotprop/pstack · skills/principle-guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
j-star-films-studios/vibecode-protocol-suite · assets/.agent/skills/engineering-principles/guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
arjitj2/open-pstack · plugins/pstack/skills/principle-guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
painhardcore/pstack · .opencode/skills/principle-guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
edbertchan/catstack · corpus/skills/principle-guard-the-context-window/SKILL.md · Apply when context is filling up: large outputs, long files, repeated reads, fan-out planning. Route bulk to subagents…
