Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add brody-0125/my-claude-skills --skill cost-trackinggit clone --depth 1 https://github.com/brody-0125/my-claude-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/brody-0125/my-claude-skills/cost-tracking)<a href="https://agentmods.dev/skills/brody-0125/my-claude-skills/cost-tracking"><img src="https://agentmods.dev/badge/skills/brody-0125/my-claude-skills/cost-tracking/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/brody-0125/my-claude-skills/cost-tracking"><img src="https://agentmods.dev/badge/skills/brody-0125/my-claude-skills/cost-tracking.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00021 | $0.00933 |
| Opus 5 | $0.00010 | $0.00466 |
| Sonnet 5 | $0.00004 | $0.00187 |
| Haiku 4.5 | $0.00002 | $0.00093 |
Grade A, and why
cost-tracking scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 115 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Cost Tracking — Model Pricing & Calculation
Provides pricing data and calculation methods for API cost estimation.
Model Pricing (per 1M tokens, USD)
| Model | Input | Output | Cache Write (5m) | Cache Read |
|---|---|---|---|---|
| claude-opus-4-6 | $5.00 | $25.00 | $6.25 | $0.50 |
| claude-sonnet-4-5 | $3.00 | $15.00 | $3.75 | $0.30 |
| claude-haiku-4-5 | $1.00 | $5.00 | $1.25 | $0.10 |
Prices as of 2026-02. Source: platform.claude.com/docs/en/about-claude/pricing. Update when pricing changes.
Cost Calculation
Per-Request Cost
cost = (input_tokens × input_price / 1_000_000) +
(output_tokens × output_price / 1_000_000) +
(cache_write_tokens × cache_write_price / 1_000_000) +
(cache_read_tokens × cache_read_price / 1_000_000)
Session Cost Estimation
When actual API token counts are unavailable, use estimates:
estimated_input_tokens = sum(tool_input_chars) / 4
estimated_output_tokens = sum(tool_result_chars) / 4
estimated_cost = estimated_input_tokens × input_price / 1_000_000 +
estimated_output_tokens × output_price / 1_000_000
Accuracy note: chars/4 estimation has ±20% error. Actual API usage data (from api_traces.jsonl) provides exact costs when available.
Budget Thresholds
| Level | Threshold | Action |
|---|---|---|
| INFO | >$0.50/session | Log to stats |
| WARNING | >$2.00/session | Alert (MEDIUM severity) |
| CRITICAL | >$10.00/session | Alert (HIGH severity) |
Cost Efficiency Metrics
| Metric | Formula | Target |
|---|---|---|
| Cost per tool call | session_cost / tool_calls | <$0.03 |
| Cost per productive call | session_cost / productive_calls | <$0.05 |
| Input/Output ratio | input_tokens / output_tokens | 3:1 to 6:1 (normal range) |
Improvement ROI Scoring
Formula for prioritizing improvement proposals:
ROI_score = (Impact × Confidence) / (Effort × Risk)
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 12d ago First seen · 115 lines · 21 tokens per session scan A 1428bd1e70f9
cost-tracking is a skill published in the GitHub repository brody-0125/my-claude-skills (2 stars, last pushed 6mo ago), licensed MIT. It adds 21 tokens to every session and 933 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
self-audit
Self-audit this skills repo against CLAUDE.md invariants, the artifact contract, and README/CLAUDE.md/docs sync via three parallel read-only subagents. Local meta-skill — independent of the /task: pipeline.
grill
Interrogate a plan or decision one question at a time before capture, keeping a decision-plus-rationale ledger, then route to the right capture skill.
architect
Answer build-or-adopt honestly, then design one committed architecture from your own understanding of the problem — driven by ranked quality attributes, stress-tested against the field and against change, proven by a walking skeleton, its consequences confirmed by the user, committed to ARCHITECTURE.md. A command the…
designer
Settle the look before the pixels — audience and context first, then the base and the delta, taste settled by looking at real states, accessibility as the floor, one design language committed to DESIGN.md as tokens with roles. A command the user types, for work with an interface someone will see; standalone, no other…
errata
Correct what was written wrong — the binding line rewritten in place, the record it came from appended to and never touched, both carrying the evidence that overturned it. Use when a run, a file, or the user contradicts something already written in a work file, a plan's contract, the glossary, or the decision index…
daily-working
End-to-end pipeline: pull a task from the project's task tracker by ID (Redmine or GitHub Issues today, more addable via a new adapter), sanity-check and impact-assess it against the codebase before touching anything, implement it with the Claude CLI, verify the result in a real browser via the Claude Chrome extension…