Context Engineering

Active Stack

echo "--- Tech Stack ---"
_rts="${CLAUDE_PLUGIN_ROOT}/scripts/resolve-tech-stack.sh"; [ -f "$_rts" ] || _rts="scripts/resolve-tech-stack.sh"
if [ -f "$_rts" ]; then bash "$_rts" --explain "$PWD" 2>&1; echo; else cat .claude/tech-stack 2>/dev/null || echo "(not set)"; fi
if [ -f .claude/tech-stack-pm ]; then echo "--- Package Manager ---"; cat .claude/tech-stack-pm; fi

Overview

Load the minimum context the current phase needs, from the right stack, and refresh it when the scope changes. The constitution (AGENTS.md / CLAUDE.md) is already loaded by the harness; do not re-read it.

When To Use

• Phase 0 of fix, batch-fix, and implement, and at every later phase boundary
• Entering an unfamiliar area, or when new files enter scope

Workflow

1. Resolve the stack for the files in scope. bash scripts/resolve-tech-stack.sh <path> is polyglot-aware (subproject .claude/tech-stack → root .claude/tech-stack.map glob → root file). Pass a representative target path, not $PWD, when the change sits in a subtree; add --check <paths> to warn when the resolved stack disagrees with the files. Then read .claude/skills/tech-stack-{stack}/SKILL.md for build/test commands and reference paths. If nothing resolves, infer with bash scripts/setup-detect.sh --json (read-only) and load the matching stack skill; if that is empty too, say the stack is unconfigured (suggest /mtk-setup) and continue in degraded mode.
2. Load references for the current phase only. Spec: domain-finance.md (finance and security supplement, only when scope touches auth/financial/infra) and the stack's testing supplement. Implementation: the stack's ## Reference Files entries for the touched layers. Review: pre-commit-review-list.md if present. Read by section where one section is enough.
3. applyTo matching. Reference entries in .claude/manifest.json may declare an applyTo glob array. Test each file in scope (the spec's change_manifest, else git diff --name-only HEAD) against the globs with case/fnmatch semantics; load the references that match at least one file and skip the rest. References without applyTo load on demand per phase. Re-run the match when new files enter scope.
4. Native paths: rules. .claude/rules/*.md carry paths: frontmatter and Claude Code loads a rule only when a matching file is read or edited. Do not read every rule up front; when the task needs a rule whose paths did not match (a security pass, a release), read that one file.
5. Read the file to be changed and 2-3 neighbours that set the local pattern.
6. Independent reads go out in one message, not sequentially.

Bound tool output before pruning instructions: instructions are prompt-cached, tool output is re-billed every turn. Model tiers per phase live in .claude/references/model-routing.md.

Verification

• Stack resolved for the files in scope (not just the repo root)
• References loaded for the current phase only; applyTo matched against real touched files
• Local pattern files read before editing or reviewing