Conciseness

The body is lean — short sections, no explanations of concepts Claude already knows, no padding. The one minor trim candidate is the TODO line ("TODO: add Linux CLI support guidance once CodexBar CLI install path is documented for Linux"), which is forward-looking scaffolding rather than actionable instruction; this keeps it just below the anchor-5 "every token earns its place" level.

Actionability

All commands are copy-paste ready and cover the common cases: both providers (`--provider codex`, `--provider claude`), both modes (`current`, `all`), both output formats, and file/stdin input (`--input /tmp/cost.json`, `--input -`). The "Current model logic" section gives precise selection rules (most recent daily row, highest-cost model, fallback to last `modelsUsed` entry, `--model` override).

Workflow Clarity

This is a simple, single-purpose skill (under 50 lines, one task: run the bundled script), and the single action is unambiguous — the script self-invokes `codexbar cost` by default, with clearly documented file/stdin alternatives and explicit fallback logic for missing `modelBreakdowns`. No destructive or batch operations are involved, so no validation checkpoints are required.

Progressive Disclosure

Clear overview with well-signaled one-level-deep references that match the actual bundle: `references/codexbar-cli.md` exists and is referenced for CLI flags/JSON fields, and `scripts/model_usage.py` exists and is used in the example commands. CLI detail is appropriately split out of the body; navigation is easy with clean section headers.

Specificity

Names several concrete actions — "summarize per-model usage for Codex or Claude", "current (most recent) model", "full model breakdown", "scriptable per-model summary from codexbar cost JSON" — within a clearly defined tool domain. Not quite the anchor-5 comprehensive coverage since it stays within a single narrow tool's cost reporting and offers no additional distinct capabilities beyond summarization variants.

Completeness

Explicitly answers both: what — "Use CodexBar CLI local cost usage to summarize per-model usage for Codex or Claude, including the current (most recent) model or a full model breakdown" — and when — "Trigger when asked for model-level usage/cost data from codexbar, or when you need a scriptable per-model summary from codexbar cost JSON". Both are concrete and clearly stated, matching the anchor-5 example pattern.

Trigger Term Quality

Good natural keyword coverage: "model-level usage/cost data", "per-model summary", "codexbar cost JSON", "codexbar" itself. A few natural synonyms users might say are missing (e.g., "spend", "spending", "token usage", "API cost"), which keeps it below the anchor-5 comprehensive-synonym level but above anchor 3's missing-variations level.

Distinctiveness Conflict Risk

Clear niche tied to a specific named tool (CodexBar) with distinct triggers ("model-level usage/cost data from codexbar"); unlikely to be confused with generic cost/usage analysis skills. The scoped tool name plus explicit provider terms (Codex, Claude) gives minimal conflict risk.