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ccacca

JSON schema

--json emits one document, the same shape for every view. All four groupings are always present; the view field names what was asked for.

Top level

Section titled “Top level”
Field Type Meaning
schema_version int Bumped when the shape changes incompatibly. Currently 1
view string summary, models, projects, daily, or sessions
window object The time range that was applied
location string The time zone used to bucket days
totals group Everything admitted by the window
main group Totals excluding sub-agent traffic
sidechain group Sub-agent traffic alone
water object The water estimate and its assumed rate
models group[] Per model, ranked by cost
projects group[] Per project directory
daily group[] Per local calendar day, oldest first
sessions group[] Per session, ranked by cost, capped by --top
unknown_models string[] Model ids with no rate. Always an array
warnings warning[] Aggregated advisories
diagnostics object What was scanned and dropped
notes string[] The accuracy caveats, in words

window

Section titled “window”
Field Type Meaning
label string Human form, e.g. all time, since 2026-09-14
since string | null RFC 3339 start, inclusive
until string | null RFC 3339 last included instant

until reports the last instant inside the window, not the exclusive bound, so filtering on it selects the same records cca did.

Group objects

Section titled “Group objects”

Used by totals, main, sidechain, and every array entry.

Field Type Meaning
key string Model id, project, date, or full session id
project string Present on session groups
title string Session title. Only present with --titles
title_source string custom, ai, or first-prompt. Only with --titles
requests int Deduplicated assistant responses
sessions int Distinct sessions in the group
projects int Distinct projects in the group
first, last string RFC 3339 bounds, omitted when undated
tokens object Exact counts
cost_usd object Unrounded dollars
water object millilitres and litres for this group
unpriced_tokens int Tokens whose model had no rate

tokens

Section titled “tokens”

input, output, cache_write_5m, cache_write_1h, cache_read, thinking, web_searches, total.

cost_usd

Section titled “cost_usd”

input, output, cache_write_5m, cache_write_1h, cache_read, web_search, total. The components sum to total.

water

Section titled “water”

Present at the top level for the whole run, and on every group. Group water needs no --titles-style opt-in: it is arithmetic on token counts rather than anything the user wrote. Because the rate is flat per token, a group’s water is exactly its tokens.total rescaled.

Field Type Meaning
ml_per_1k_tokens number The rate actually used
millilitres, litres number The estimate
equivalence string The lighthearted comparison

warnings

Section titled “warnings”
Field Type Meaning
kind string e.g. unknown-model, fast-mode-anomaly
subject string What it concerns
count int How many records
detail string A sentence explaining it

diagnostics

Section titled “diagnostics”

files, lines, records, duplicates, skipped (by reason), flat_cache_fallback, cache_split_mismatch, bad_timestamp, no_dedup_key, filtered_by_window, undated.

Titles

Section titled “Titles”

title and title_source appear on session groups only, and only when --titles is passed. The title is the full text; the table view truncates for display but the document does not. See Session titles.

Stability

Section titled “Stability”

schema_version is bumped when a change would break a consumer. Adding a field is not such a change, so read defensively. Empty collections are [] rather than null, so you can iterate without a nil check.

A complete document

Section titled “A complete document”

Arrays trimmed to one entry each; everything else is verbatim.

{
  "schema_version": 1,
  "view": "models",
  "window": {
    "label": "all time",
    "since": null,
    "until": null
  },
  "location": "Local",
  "totals": {
    "requests": 340,
    "sessions": 13,
    "projects": 3,
    "first": "2026-09-05T09:07:00Z",
    "last": "2026-09-18T19:25:00Z",
    "tokens": {
      "input": 144544,
      "output": 673457,
      "cache_write_5m": 503032,
      "cache_write_1h": 6599068,
      "cache_read": 52044613,
      "thinking": 135109,
      "web_searches": 0,
      "total": 59964714
    },
    "cost_usd": {
      "input": 0.39251900000000023,
      "output": 8.951250000000007,
      "cache_write_5m": 1.5278349999999992,
      "cache_write_1h": 35.93335000000003,
      "cache_read": 14.017779100000006,
      "web_search": 0,
      "total": 60.82273309999998
    }
  },
  "main": {
    "requests": 305,
    "sessions": 13,
    "projects": 3,
    "first": "2026-09-05T09:07:00Z",
    "last": "2026-09-18T19:25:00Z",
    "tokens": {
      "input": 141138,
      "output": 651462,
      "cache_write_5m": 450532,
      "cache_write_1h": 6599068,
      "cache_read": 50894030,
      "thinking": 135109,
      "web_searches": 0,
      "total": 58736230
    },
    "cost_usd": {
      "input": 0.3891130000000003,
      "output": 8.841275000000005,
      "cache_write_5m": 1.462209999999999,
      "cache_write_1h": 35.93335000000003,
      "cache_read": 13.902720800000004,
      "web_search": 0,
      "total": 60.528668799999984
    }
  },
  "sidechain": {
    "requests": 35,
    "sessions": 5,
    "projects": 3,
    "first": "2026-09-05T10:18:00Z",
    "last": "2026-09-18T15:19:00Z",
    "tokens": {
      "input": 3406,
      "output": 21995,
      "cache_write_5m": 52500,
      "cache_write_1h": 0,
      "cache_read": 1150583,
      "thinking": 0,
      "web_searches": 0,
      "total": 1228484
    },
    "cost_usd": {
      "input": 0.003406,
      "output": 0.10997499999999999,
      "cache_write_5m": 0.06562500000000004,
      "cache_write_1h": 0,
      "cache_read": 0.1150583,
      "web_search": 0,
      "total": 0.2940643
    }
  },
  "water": {
    "ml_per_1k_tokens": 0.3,
    "millilitres": 17989.4142,
    "litres": 17.9894142,
    "equivalence": "about 2 minutes of shower"
  },
  "models": [
    {
      "key": "claude-opus-5",
      "requests": 101,
      "sessions": 8,
      "projects": 2,
      "first": "2026-09-06T11:04:00Z",
      "last": "2026-09-18T18:28:00Z",
      "tokens": {
        "input": 49531,
        "output": 219438,
        "cache_write_5m": 138450,
        "cache_write_1h": 2243392,
        "cache_read": 17672752,
        "thinking": 41667,
        "web_searches": 0,
        "total": 20323563
      },
      "cost_usd": {
        "input": 0.24765500000000001,
        "output": 5.48595,
        "cache_write_5m": 0.8653125000000003,
        "cache_write_1h": 22.433919999999997,
        "cache_read": 8.836375999999996,
        "web_search": 0,
        "total": 37.86921349999999
      }
    }
  ],
  "projects": [
    {
      "key": "-home-dev-payments-api",
      "requests": 95,
      "sessions": 4,
      "projects": 1,
      "first": "2026-09-06T11:04:00Z",
      "last": "2026-09-18T18:28:00Z",
      "tokens": {
        "input": 45085,
        "output": 196981,
        "cache_write_5m": 134106,
        "cache_write_1h": 2051770,
        "cache_read": 15188227,
        "thinking": 39217,
        "web_searches": 0,
        "total": 17616169
      },
      "cost_usd": {
        "input": 0.16629599999999994,
        "output": 3.7905300000000013,
        "cache_write_5m": 0.5942050000000001,
        "cache_write_1h": 15.215708000000001,
        "cache_read": 5.7395396000000005,
        "web_search": 0,
        "total": 25.506278600000005
      }
    }
  ],
  "daily": [
    {
      "key": "2026-09-05",
      "requests": 22,
      "sessions": 1,
      "projects": 1,
      "first": "2026-09-05T09:07:00Z",
      "last": "2026-09-05T10:27:00Z",
      "tokens": {
        "input": 5763,
        "output": 33186,
        "cache_write_5m": 35593,
        "cache_write_1h": 304427,
        "cache_read": 2550059,
        "thinking": 5257,
        "web_searches": 0,
        "total": 2929028
      },
      "cost_usd": {
        "input": 0.008548,
        "output": 0.252575,
        "cache_write_5m": 0.060432500000000014,
        "cache_write_1h": 0.9260259999999999,
        "cache_read": 0.4037712,
        "web_search": 0,
        "total": 1.6513527000000001
      }
    }
  ],
  "sessions": [
    {
      "key": "070d7109-26b1-4973-8e7a-ce7677216e9e",
      "project": "-home-dev-payments-api",
      "requests": 38,
      "sessions": 1,
      "projects": 1,
      "first": "2026-09-15T11:06:00Z",
      "last": "2026-09-15T14:38:00Z",
      "tokens": {
        "input": 19242,
        "output": 77500,
        "cache_write_5m": 47183,
        "cache_write_1h": 833766,
        "cache_read": 6156420,
        "thinking": 16438,
        "web_searches": 0,
        "total": 7134111
      },
      "cost_usd": {
        "input": 0.07875800000000001,
        "output": 1.588445,
        "cache_write_5m": 0.2396525,
        "cache_write_1h": 6.785294000000001,
        "cache_read": 2.3950386,
        "web_search": 0,
        "total": 11.087188100000004
      }
    }
  ],
  "unknown_models": [],
  "warnings": [],
  "diagnostics": {
    "files": 18,
    "lines": 450,
    "records": 340,
    "duplicates": 110,
    "skipped": {},
    "flat_cache_fallback": 0,
    "cache_split_mismatch": 0,
    "bad_timestamp": 0,
    "no_dedup_key": 0,
    "filtered_by_window": 0,
    "undated": 0
  },
  "notes": [
    "Cost is what this usage would cost at API rates, not what you were billed; Claude Code on a subscription draws from your plan allowance instead.",
    "Water assumes 0.30 mL / 1k tokens, a rough estimate."
  ]
}