name: speckit-optimize-tokens description: Track and report token usage across extensions and governance files. compatibility: Requires spec-kit project structure with .specify/ directory metadata: author: github-spec-kit source: optimize:commands/speckit.optimize.tokens.md
User Input
$ARGUMENTS
You MUST consider the user input before proceeding (if not empty).
Arguments: --diff to compare against the previous report, --extensions-only to skip governance files.
Goal
Measure the token footprint of every governance document and extension command that AI agents load during sessions. Produce a token usage report with per-file costs, per-extension rankings, session load estimates, and historical trends. Suggest optimizations but apply nothing without user consent.
This command answers: "How much of my AI context window is consumed by governance and tooling overhead before any actual work begins?"
Operating Constraints
- Suggest-only: NEVER modify any file without explicit user consent. This command is read-only by default.
- Spec-kit standard paths: Start from
.specify/as the source of truth. Discover tool-specific files (CLAUDE.md,AGENTS.md,.github/copilot-instructions.md) by checking if they exist. - Reproducible estimates: Token estimation uses chars ÷
chars_per_token(default: 4.0, configurable). Note this is approximate — actual tokenizer counts vary by model. Lower ratios (3.0–3.5) give more conservative estimates for code-heavy files.
Execution Steps
1. Discover Governance Files
Scan for all files that AI agents may load on session start or command invocation:
Always-loaded files (loaded on every AI session):
CLAUDE.md(if present — Claude Code sessions)AGENTS.md(if present — generic agent sessions).github/copilot-instructions.md(if present — Copilot sessions)
Constitution chain:
.specify/memory/constitution.md— read to check if it is a redirect or contains content- If redirect, follow to the actual file (e.g.,
.ai/rules/constitution.md) - Record both the pointer and the target
Supplementary governance files:
- Glob
.ai/rules/*.md(if directory exists) - Glob
.specify/memory/*.md(beyond constitution) - Any other files referenced from the always-loaded files (parse for markdown links and "Read and follow" patterns)
For each file: record path, exists (bool), size in bytes, size in characters, estimated tokens (chars ÷ chars_per_token).
2. Inventory Extension Commands
For each extension listed in .specify/extensions.yml → installed::
- Read
.specify/extensions/<ext-id>/extension.yml - For each command in
provides.commands[]:- Locate the command file (the
file:field points to the source) - Measure its character count and estimated tokens
- Locate the command file (the
- Sum total tokens per extension
Produce a ranked list of extensions by total token footprint.
3. Calculate Per-Session Load Estimates
Estimate what gets loaded for different session types:
Baseline session (always loaded):
- Sum tokens of always-loaded governance files
- This is the minimum overhead before any work begins
Constitution-aware session (baseline + constitution):
- Add constitution chain tokens
- Add supplementary governance file tokens
Command invocation (per command):
- For each extension command, the cost is: baseline + command file tokens + any files the command references (parse "Read" / "Load" instructions in the command file)
Present estimates for each context window size in context_window_sizes config (default: 8K, 32K, 128K, 200K, 1M).
### Per-Session Token Budget
| Session Type | Tokens | % of 8K | % of 32K | % of 128K | % of 200K | % of 1M |
|---|---|---|---|---|---|---|
| Baseline (governance only) | X | X% | X% | X% | X% | X% |
| + Constitution | X | X% | X% | X% | X% | X% |
| + Largest command | X | X% | X% | X% | X% | X% |
4. Historical Trend Analysis
Check for a previous report at .specify/optimize/token-report.md.
If found:
- Parse the previous report's per-file token counts
- Compare each file: current vs previous
- Calculate per-file growth/reduction
- Flag files growing faster than
file_growth_percentthreshold (default: 20%) - Show overall governance token trend (growing / stable / shrinking)
If not found:
- Note this is the first run — no trend data available
- Recommend running periodically to track trends
5. Generate Token Usage Report
Present the full report to the user:
## Token Usage Report
**Date**: <ISO date>
**Target Context Window**: <from config> tokens
### Governance Files
| File | Exists | Chars | Est. Tokens | Load Timing | Notes |
|---|---|---|---|---|---|
| CLAUDE.md | Yes/No | X | X | Always | — |
| .specify/memory/constitution.md | Yes/No | X | X | Always | Redirect to <path> |
| <actual constitution path> | Yes | X | X | Always | Actual content |
| AGENTS.md | Yes/No | X | X | Always | — |
| .github/copilot-instructions.md | Yes/No | X | X | Always | — |
| .ai/rules/<file>.md | Yes | X | X | On reference | — |
**Total governance tokens**: X (~Y% of <context_window>)
### Extension Commands (ranked by token cost)
| Extension | Commands | Total Tokens | Largest Command | Largest Tokens |
|---|---|---|---|---|
| <ext-id> | X | X | <cmd> | X |
| ... | ... | ... | ... | ... |
**Total extension tokens**: X (loaded per invocation, not per session)
### Per-Session Estimates
[Table from Step 3]
### Historical Trend
| File | Previous | Current | Change | Growth % | Flag |
|---|---|---|---|---|---|
| <path> | X | X | +/-X | X% | [!] if > threshold |
**Overall governance trend**: Growing / Stable / Shrinking (X% change)
### Optimization Suggestions
[Ranked by projected token savings — suggest only, do not apply]
1. **<suggestion>**: <description> — saves ~X tokens
2. ...
6. Save Report
Ask the user: "Save this report to .specify/optimize/token-report.md for trend tracking?"
If approved:
- Write the report to
.specify/optimize/token-report.md(create directory if needed) - This enables historical trend comparison on future runs
If declined:
- Report is displayed in conversation only, not persisted
7. Suggest Next Steps
Based on findings:
### Recommended Actions
- If governance budget exceeds threshold → suggest `/speckit.optimize.run` for full audit
- If specific extensions are oversized → suggest reviewing those command files for compression
- If CLAUDE.md duplicates constitution → suggest consolidation
- If growth trend is upward → suggest scheduling periodic token audits
Operating Principles
Read-Only Default
This command reads and measures — it does not modify. The only write action is saving the report file, and only with explicit consent.
Consistent Estimation
Token counts use chars ÷ chars_per_token (configurable, default: 4.0) throughout. This is an approximation — actual counts vary by tokenizer. Use 3.0–3.5 for code-heavy projects, 4.0 for prose-heavy. The approximation is consistent across runs, making trend analysis valid even if absolute numbers are approximate.
Actionable Output
Every metric in the report is paired with a concrete action: "X tokens in version history → remove via /speckit.optimize.run". Raw numbers without actions are noise.
Trend Over Snapshots
A single run provides a snapshot. Repeated runs provide a trend. The historical comparison is the most valuable output — it tells you whether your governance is growing, stable, or shrinking over time.