| name | context-pack-builder |
| description | Use to prepare bounded context packs for stateless subagents, selecting only required specs, diffs, artifacts, constraints, allowed scope, forbidden scope, validation requirements, and output contracts. |
Context Pack Builder
Purpose
Create minimal but sufficient context packs so subagents can run one bounded job without inheriting long chat history or stale artifacts.
Script-First Execution
After selecting candidate sources, build deterministic source metadata before handing the pack to a subagent:
python agent-skills/context-pack-builder/scripts/build_context_manifest.py --repo-root . --json <source> [<source> ...]
The helper checks file existence, source kind, relative path, byte size, line count, SHA-256, missing sources, directories, outside-repo paths, and per-file size warnings. Use this as the manifest evidence layer; use LLM judgement to decide inclusion rationale, exclusions, compact prior findings, allowed scope, forbidden scope, validation requirements, and output contract.
Run the helper from Windows PowerShell or a POSIX shell (Linux/macOS) with the same command shape; use python3 when python is unavailable.
Prompt / Handoff Contract
When building a context pack for a subagent, use the shared stable-prefix / dynamic-run-packet shape from agent-skills/README.md. Treat this as a handoff recommendation, not a new file format or schema requirement.
Stable prefix:
- Skill:
context-pack-builder
- Execution Profile:
hybrid
- Reusable Rules: subagents are stateless, scope must be bounded, and missing or stale artifacts must be explicit.
- Scope / Governance Defaults: allowed scope, forbidden scope, validation requirements, output contract, and human-decision boundaries.
- Output Contract: included sources, excluded sources, compact prior findings, stale or missing artifact warnings, and next recipient.
Dynamic run packet:
- User Request:
- Deterministic Evidence:
- Relevant Files Or Artifacts:
- Current Assumptions Or Gaps:
- Requested Judgement Or Transformation:
Keep source snippets and command output in the dynamic run packet after the stable prefix so repeated handoff instructions remain cache-friendly.
Workflow
- Read the selected job, atomic item metadata, spec refs, dependency notes, allowed scope, forbidden scope, and output contract.
- Identify required source files, artifacts, tests, diffs, prior findings, and human decisions.
- Run deterministic manifest building for selected source paths when available.
- Exclude unrelated history, obsolete drafts, closed objections, and out-of-scope files.
- Summarize prior findings only as durable references or compact handoff notes.
- Record included and excluded sources.
- Note token budget, stale artifacts, missing sources, and assumptions.
- Hand the context pack to
atomic-subagent-runner or the root orchestrator.
Mandatory Rules
- Include enough context to execute the job, but not the whole long conversation.
- Do not include private or unrelated context unless explicitly required and allowed.
- Stale or missing artifacts must be called out.
- The context pack must state allowed scope and forbidden scope.
- The output contract must be explicit.
Boundaries
- Do not execute the job.
- Do not modify project files except a requested context-pack artifact.
- Do not resolve ambiguity by padding the pack with everything.
Validation
Check:
- Job ID and atomic item ID are present.
- Spec refs are present.
- Included/excluded source list is present.
- Allowed and forbidden scopes are explicit.
- Validation requirements are explicit.
- Missing or stale context is reported.
- If the manifest helper changed, run its unit tests and a CLI smoke check.
Output
Use this report template:
### Context Pack Report
- context pack manifest:
- stable prefix / dynamic run packet, when handing off to a subagent:
- included sources:
- excluded sources:
- compact prior findings:
- allowed scope:
- forbidden scope:
- validation requirements:
- output contract:
- stale or missing artifact warnings:
