Measured Against Codex 0.144.4
The helper reproduces the installed renderer’s UTF-8 byte accounting, line costs, aliases, truncation, and omission behavior. It fails closed if the Codex version changes.
Codex Runtime · Skill Library
Skill Budget Findings & Status
The catalog now has an exact, version-pinned measurement tool. The current runtime fits every skill name and path, but it has only 95 tokens of headroom before Codex begins omitting skills and must shorten descriptions to stay inside its fixed 2% allocation.
Implemented and independently verified
338%Full catalog over budget · goal 0%
95Tokens before skill omissions
342 / 342Skills visible now
0Skills omitted now
Executive Takeaway
For overage, lower is better: the goal is 0% over. Full descriptions require 22,625 tokens against a 5,168-token budget, which is 338% over. The minimum names-and-paths representation requires 5,073 tokens, which is 1.84% under budget. Utilization must remain below 100%; the recommended safety target is 90% or less.
Current Readiness
Exact Measurement Is Ready
Fresh Runtime Verification
Live output matched both the visible skill count and every included skill path: count delta 0, path delta 0, with no missing skill files.
Historical Replay Supported
A saved Codex session can be replayed to quantify an earlier warning, including its reported omitted count. Stale or mismatched replays are rejected.
Validation Passed
118 tests passed across 15 files. Type checking, focused budget tests, skill validation, linting, and whitespace checks also passed.
Numerical Findings
Budget Views Compared
Space needed to render is what the skill catalog would consume. Space Codex allows is the fixed 2% cap. When the needed space is larger, Codex shortens descriptions first and then omits skills.
| View | Space needed to render | Space Codex allows | Utilization | Result |
|---|---|---|---|---|
| Minimum names + paths | 5,073 tokens | 5,168 tokens | 98.16% | 95 tokens under |
| Full descriptions | 22,625 tokens | 5,168 tokens | 438% | 17,457 tokens / 338% over |
| Context-window share | 8.76% | 2.00% | — | 6.76 percentage points over |
Key Timeline
What Changed
Observed
Codex warned that skill descriptions were removed and 137 additional skills were omitted in an earlier session.
Diagnosed
The 2% allocation was confirmed as a hard-coded renderer budget, not a configurable setting.
Implemented
codex-skill-budget.ts was added to skill-librarian with fresh and historical measurement modes.Verified Now
The live catalog reports 342 visible skills, zero omissions, and shortened descriptions. The earlier 137-skill omission is not reproduced by the current catalog.
Risks / Watch Items
The Current Margin Is Fragile
One Small Catalog Change Can Regress
The minimum representation is already at 98.16% utilization. A modest increase in paths, aliases, or skill count can force omissions again.
Renderer Drift Must Be Explicit
The calculator intentionally stops on an unsupported Codex version. The constants and verification tests should be reviewed whenever Codex upgrades.
Recommended Next Moves
Create Deliberate Headroom
1 · Reduce Active Catalog Scope
Target minimum utilization below 90%. That requires removing at least 422 rendered tokens from the implicit catalog while preserving on-demand availability.
2 · Add A Regression Threshold
Run the exact calculator in maintenance or CI and flag growth before minimum utilization crosses the selected safety threshold.