Files
claude-foundations/memory/decisions.md
Paul O'Reilly 52b0f2b5c6 Add session log and reflect: API design research session
Session log for 2026-03-29 covering API/LLM security research, agent-runtimes
audit, and review skill creation. Reflected into:
- decisions.md: best-practices topic split, review skills read-only design
- process-lessons.md: background agents for research, Edit context
  disambiguation, best-practices repo location

Pruned 2 old reflected logs (2026-03-17, 2026-03-18).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-29 11:22:37 +13:00

86 lines
5.4 KiB
Markdown

# Architecture & Design Decisions
## Knowledge Pipeline: Separate /reflect-logs from /reflect
`/reflect-logs` handles continuous log processing; `/reflect` handles milestone reflections. Different purpose, different cadence — combining them would overcomplicate the milestone skill.
## Knowledge Pipeline: MD5 for reflection state, git SHAs for distill state
Log files may not be committed when reflected on, so MD5 of file content is the right identity. `/distill-best-practices` works across committed repos, so git SHAs are appropriate there.
## Knowledge Pipeline: Pruning happens in /log, not /reflect-logs
`/log` runs most frequently (every session end), so it naturally keeps the log directory clean as a side effect.
## Knowledge Pipeline: /distill-best-practices is interactive
Cross-project convention changes need human judgment. The skill proposes updates and waits for approval before writing.
## Session Logs: Timestamp-based IDs (HHMMSS)
Human-readable, naturally sorted, no external dependencies. Format: `YYYY-MM-DD.HHMMSS.md`.
## Linting: Formatter exit codes vs hook exit codes
Formatter scripts exit 1 on lint errors. The dispatcher hook decides the final exit code (exit 2 for PostToolUse feedback). This separates formatter logic from hook semantics — same scripts work for both PostToolUse and pre-commit.
## Linting: Checkpoint via git hash-object with .pre-lint sidecar
Fast (~1ms), no commits or stash needed, orphan blobs auto-GC'd. Falls back to `cp` outside git repos.
## Linting: Project opt-in via formatter symlinks
Projects opt in by having a `formatters/` directory with symlinks back to canonical scripts. Zero-config, visible in `ls`, no parsing needed. The hook walks up the directory tree to find `formatters/`.
## Skills: Use CLAUDE_PROJECT_ROOT for cross-project path resolution
Skills that reference files outside their own project (e.g., `/distill-best-practices` reading settings.yaml) use `CLAUDE_PROJECT_ROOT` env var instead of hardcoded `~/dev/claude/` or relative `../` paths. Makes skills portable across users. Env var exported in `~/.bashrc`, with runtime fallback (walk up directory tree to find highest CLAUDE.md).
## Skills: settings.yaml paths relative to project root
`settings.yaml` uses relative paths (`projects_dir: projects`) rather than absolute paths. Combined with `CLAUDE_PROJECT_ROOT`, this keeps config portable. The `extra_projects` section handles projects outside the standard `projects_dir` (e.g., `small-scripts` at root level).
## CLAUDE.md: Remove technology-specific sections from root
Ansible and Helm sections removed from root CLAUDE.md — already covered with more detail in `best-practices/ansible.md` and `best-practices/helm.md`. Technology-specific practices belong in best-practices, not root guidelines.
## context-load: Walk upward collecting context files
Walks from cwd upward collecting CLAUDE.md, CONTEXT.md, MEMORY.md, BESTPRACTICES.md at each level. Gives hierarchical context inheritance — highest ancestor provides global guidelines, project dir provides specifics.
## context-load: Dedup via readlink -f
Root CLAUDE.md is a symlink to claude-foundations. Without dedup it would load twice. `readlink -f` resolves all symlinks before comparison.
## context-load: Tree depth 3
Deep enough to show project structure without overwhelming output. Applied at every CLAUDE.md location.
## CONTEXT.md follows MEMORY.md pattern
Thin index + `context/` folder. Consistency with MEMORY.md. CONTEXT.md focuses on active work for agent orientation; MEMORY.md on accumulated learnings.
## Status line: Per-session topic files keyed by session ID
Topic files at `~/.claude/status/<session-id>/claude-topic.txt`. Session ID uniquely identifies each session, allowing multiple concurrent sessions to have independent topics without collisions.
## Status line: Bridge session ID via /tmp file
Claude has no direct access to its own session ID. The status line script writes it to `/tmp/claude-session-id-<md5 of cwd>`, which `set-topic.sh` reads to find the correct per-session topic directory.
## Status line: Pending-topic queue for bootstrap race condition
`set-topic.sh` is called on the first message, before `statusline.sh` has written the session ID file. Instead of erroring, it writes to `/tmp/claude-pending-topic-<hash>`. `statusline.sh` picks this up on its next run via `mv` (atomic, no double-application). Simple and self-healing — statusline already runs after every response.
## Status line: Config must exist in every profile settings file
Each profile (`~/.claude`, `~/.claude-octopus`, `~/.claude-oreillyit`) has its own `settings.json` with no inheritance. The `statusLine` entry and `Bash(~/.claude/status/set-topic.sh:*)` permission must be added to each independently.
## Best practices: One file per topic, not combined mega-documents
api-design.md and llm-code-security.md are separate files despite both being "security-adjacent". API design covers versioning, pagination, idempotency — not just security. Self-contained topic files are independently referenceable and can be loaded selectively by skills and agents.
## Review skills: Read-only output, not auto-edit
/review-plan and /review-spec are read-only (allowed-tools: Read, Glob, Grep). Review output informs the human rather than auto-editing plans/specs. This avoids unintended changes and reduces permission prompts. Both skills load all 5 design/security best practice files upfront — better to over-load context than miss a relevant check.