"Performance profiling — find bottlenecks, measure against budgets, produce ranked optimization recommendations."
Install
npx skillscat add sneakkestrel16/mininginc/perf-profile Install via the SkillsCat registry.
!bash "${CLAUDE_SKILL_DIR}/../../hooks/yaml-helper.sh" resolve_config --keys performance.enforce,automation,workflow
Resolved above — use as-is. No block → defaults in.claude/docs/config-resolution.md.
Performance Profile
Every AskUserQuestion call follows .claude/docs/automation-modes.md
(collaborative asks always · guided major-only · autonomous logs and proceeds;automation_always_ask categories always prompt).
Insufficient input — check this before producing any report
If the inputs this skill needs do not exist, the answer is "could not run" —
not a filled-in report. Check first, and stop if the check fails.
- List the inputs this skill reads (data files, prior reports, profiler output,
test results, registries, source code). - For each, record
FOUNDorABSENT— not "assumed present". - If any input required for a section is ABSENT, that section is
NOT ASSESSED — NO DATA. Do not estimate it, do not infer it from an
adjacent artifact, and do not leave a mandated cell to be filled by whoever
reads the template next. - If every required input is ABSENT, stop and report
NOT ASSESSED — NO DATAas the whole verdict, naming what was missing and
which skill produces it.
A verdict of NOT ASSESSED is a success. It is the correct, useful answer to
"what does the data say?" when there is no data. The failure mode this prevents is
specific: a report whose verdict enum has no "could not run" state produces
false clean passes — an asset audit returning COMPLIANT on a project with no
assets and no standards, or a performance profile reporting ">99% headroom against
a 16.67ms budget" with zero profiler data and no budget ever set.
Absence of evidence is never evidence of absence. A scan that finds no
matches because there are no files to scan has not verified anything. Say which of
the two happened — a reader cannot tell from a green result.
Phase 0: Resolve Budget Enforcement
performance.enforce decides what a budget violation means in this run. It
does not change which budgets are measured — performance.target_framerate,frame_budget_ms, draw_call_limit and memory_ceiling_mb are profiled the
same way at every level:
| Value | Effect on this profile's findings |
|---|---|
warn (default) |
Violations are reported as findings. They do not block; CI logs them without failing. |
block |
Violations are blockers. Say so explicitly in the report — a block project treats an over-budget system as release-stopping, and /gate-check will FAIL the Polish gate on it. |
off |
Budgets are informational only. Still report measured values, but do not raise violations as findings or recommendations to fix. |
Only warn, block and off are recognized. Surface any other value to the
user and fall back to warn rather than guessing.
The value is locally overridable (
/settings --local performance.enforce=block),
so use the resolved block above rather than readingproject.yaml— a
teammate's stricter local setting is meant to bite on their machine only.
Phase 1: Determine Scope
Read the argument:
- System name → focus profiling on that specific system
full→ run a comprehensive profile across all systems
Phase 2: Load Performance Budgets
Read the committed budgets from config first — they are the project's
record of what it agreed to, and design docs are the fallback, not the source:
bash "${CLAUDE_SKILL_DIR}/../../hooks/yaml-helper.sh" get_effective_yaml_key performance.target_framerate
bash "${CLAUDE_SKILL_DIR}/../../hooks/yaml-helper.sh" get_effective_yaml_key performance.frame_budget_ms
bash "${CLAUDE_SKILL_DIR}/../../hooks/yaml-helper.sh" get_effective_yaml_key performance.draw_call_limit
bash "${CLAUDE_SKILL_DIR}/../../hooks/yaml-helper.sh" get_effective_yaml_key performance.memory_ceiling_mbRun each line as its own plain command, one key per call: the helper moves to
the project root itself, so it works when the session was started in a
subfolder, and this skill pre-approves that form only (a source or cd ... &&
wrapper asks the user every time). Empty output means that budget is not set.
Resolve these budgets from
project.yaml, not from prose. Phase 0 above
states these four budgets "are profiled the same way at every level". A user
who setperformance.target_framerate: 60inproject.yamlhas it ignored if
the budget is read from design docs or CLAUDE.md instead.
Then fall back to design docs or CLAUDE.md for anything config does not carry:
- Target FPS (e.g., 60fps = 16.67ms frame budget)
- Memory budget (total and per-system)
- Load time targets
- Draw call budgets
- Network bandwidth limits (if multiplayer)
A metric with no committed budget is NOT ASSESSED, not a pass. Do not
measure against the template's [16.67ms] placeholder — an unset budget is not
a budget that was met, and reporting headroom against a number nobody chose is
the exact fabrication this skill's own header warns about.
Phase 3: Analyze Codebase
CPU Profiling Targets:
_process()/Update()/Tick()functions — list all and estimate cost- Nested loops over large collections
- String operations in hot paths
- Allocation patterns in per-frame code
- Unoptimized search/sort over game entities
- Expensive physics queries (raycasts, overlaps) every frame
Memory Profiling Targets:
- Large data structures and their growth patterns
- Texture/asset memory footprint estimates
- Object pool vs instantiate/destroy patterns
- Leaked references (objects that should be freed but aren't)
- Cache sizes and eviction policies
Rendering Targets (if applicable):
- Draw call estimates
- Overdraw from overlapping transparent objects
- Shader complexity
- Unoptimized particle systems
- Missing LODs or occlusion culling
I/O Targets:
- Save/load performance
- Asset loading patterns (sync vs async)
- Network message frequency and size
Phase 4: Generate Profiling Report
Write the report to production/polish/[scope]-report-[date].md, asking first
per the Collaboration Protocol: "May I write this profiling report toproduction/polish/[scope]-report-[date].md?" Create the directory if absent.
Name the destination — do not just render the template into the
conversation. A profile that lives only in the transcript is gone the moment
the session ends, and no two runs can be compared.production/polish/
is the same location/team-polishwrites, deliberately: a profile taken by
either route belongs in one place, or the comparison this skill exists to enable
cannot be made.If a
NOT ASSESSEDsection survives into the report, keep it in the written
file. A profile whose gaps are edited out on the way to disk reads, later, as a
complete measurement.
## Performance Profile: [System or Full]
Generated: [Date]
### Performance Budgets
| Metric | Budget | Estimated Current | Status |
|--------|--------|-------------------|--------|
| Frame time | [16.67ms] | [estimate] | [OK/WARNING/OVER/NOT ASSESSED] |
| Memory | [target] | [estimate] | [OK/WARNING/OVER/NOT ASSESSED] |
| Load time | [target] | [estimate] | [OK/WARNING/OVER/NOT ASSESSED] |
| Draw calls | [target] | [estimate] | [OK/WARNING/OVER/NOT ASSESSED] |
### Hotspots Identified
| # | Location | Issue | Estimated Impact | Fix Effort |
|---|----------|-------|------------------|------------|
### Optimization Recommendations (Priority Order)
1. **[Title]** — [Description]
- Location: [file:line]
- Expected gain: [estimate]
- Risk: [Low/Med/High]
- Approach: [How to implement]
### Quick Wins (< 1 hour each)
- [Simple optimization 1]
### Requires Investigation
- [Area that needs actual runtime profiling to confirm impact]Output the report with a summary: top 3 hotspots, estimated headroom against
each budget that is set — for a metric with none, no budget set — headroom not assessed — and recommended next action.
Phase 5: Scope and Timeline Decision
Activate this phase only if any hotspot has Fix Effort rated M or L.
Present significant-effort items and ask the user to choose for each:
- A) Implement the optimization (proceed with fix now or schedule it — at
workflow: minimal, which has no sprints, add it to the brief's build order) - B) Reduce feature scope (run
/scope-check [feature]to analyze trade-offs) - C) Accept the performance hit and defer to Polish phase (log as known issue)
- D) Escalate to technical-director for an architectural decision (run
/architecture-decision)
If multiple items are deferred to Polish (choice C), record them under ### Deferred to Polish.
Verdict
Close every run that produced a report — whether or not Phase 5 ran — with:
Verdict: COMPLETE — performance profile generated (saved toproduction/polish/[scope]-report-[date].md if the write was approved). The only
other outcome is the NOT ASSESSED — NO DATA path above.
Phase 6: Next Steps
- If bottlenecks require architectural change: run
/architecture-decision. - If scope reduction is needed: run
/scope-check [feature]. - To schedule optimizations: run
/sprint-plan update(atworkflow: minimal, which has no sprints, add them to the brief's build order instead).
Rules
- Never optimize without measuring first — gut feelings about performance are unreliable
- Recommendations must include estimated impact — "make it faster" is not actionable
- Profile on target hardware, not just development machines
- Static analysis (this skill) identifies candidates; runtime profiling confirms