Cost Report

cost-report — LLM Cost Breakdown

Generate a human-readable (or machine-readable) cost report from Hermes' usage logs.

Procedure

1. Export logs. Run:

``bash hermes logs export --since ${WINDOW} --format jsonl --output /tmp/hermes-logs.jsonl ``

1. Parse and aggregate. Using DuckDB (preferred) or jq + awk:

```bash duckdb -c " CREATE TABLE logs AS SELECT * FROM readjsonauto('/tmp/hermes-logs.jsonl');

-- By provider SELECT provider, SUM(costusd) AS cost, SUM(tokensin) AS tokin, SUM(tokensout) AS tok_out, COUNT(*) AS calls FROM logs GROUP BY 1 ORDER BY 2 DESC; " ```

1. Produce four tables:

A. By provider `` Provider Cost($) Tokens-in Tokens-out Calls anthropic 18.44 2.1M 380K 412 openai 6.20 1.2M 220K 187 cerebras 0.45 890K 140K 523 ``

B. By gateway `` Gateway Cost($) % of total telegram 14.22 56% cli 8.10 32% discord 2.77 11% cron 0.50 2% ``

C. By active skill `` Skill Cost($) Calls Avg-cost claude-code 9.40 22 $0.43 lightrag-query 4.11 189 $0.02 pr-review 3.20 8 $0.40 weekly-dep-audit 1.25 1 $1.25 ``

D. Daily trend (simple ASCII sparkline) `` Mon ▂ Tue ▃ Wed ▅█ ← weekly-dep-audit ran Thu ▃ Fri ▄ Sat ▂ Sun ▁ Total: $25.53 ``

1. Flag anomalies. Use a 3x median-absolute-deviation rule on daily spend. Note any days or skills that exceed the threshold:

> ⚠ Wed spent $9.80, 4.5x typical. Driven by weekly-dep-audit.

1. Recommend savings. Pattern-match the data:

• Any single skill > 30% of weekly cost → suggest a cheaper model for that skill
• Input tokens > 10x output tokens on any provider → suggest prompt caching
• Repeated Claude skills/SOUL prefixes without cache hits → enable v0.14 1-hour prefix caching
• Gemini calls without google/gemini-3.1-flash on classification-ish intents → suggest routing
• Grok 4.3 / GPT-5.5 / Opus calls in cron or triage lanes → require explicit opt-in routing

1. Deliver. Post to private notification channel. Attach the raw JSON if format is json.

Cron wiring

- name: weekly-cost-report
  schedule: "0 9 * * 1"
  task: /cost-report window=7d format=markdown
  notify: telegram_private

See also

• [Part 20: Observability & Cost](../../../part20-observability.md)
• [cost-routing playbook](../../../part20-observability.md#cost-routing-playbook-the-one-that-actually-saves-money)

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: OnlyTerp
• Source: OnlyTerp/hermes-optimization-guide
• License: MIT

Install and usage instructions live in the source repository linked above.