Analysis of 12 sessions across 8 days reveals that cache operations dominate costs (90.5% of total), not output generation (9.2%). The biggest cost driver is Tether's large constitutional context (~50K tokens) being loaded on every API call. Here are the key findings:
| Component | Tokens | Rate (per MTok) | Est. Cost | % of Total | Data |
|---|---|---|---|---|---|
| Cache Read Reading cached context on each API call |
1,248,656,731 | $1.50 | $1,873 | 50.3% | REAL DATA |
| Cache Create Writing new context to cache |
79,799,267 | $18.75 | $1,496 | 40.2% | REAL DATA |
| Output Tether's generated responses + code |
4,569,351 | $75.00 | $343 | 9.2% | REAL DATA |
| Input Non-cached prompt tokens |
930,200 | $15.00 | $14 | 0.4% | REAL DATA |
| TOTAL | — | — | $3,726 | 100% | ESTIMATE |
| Session | Date | Duration | User Msgs | Subagents | Output Tokens | Est. Cost | $/Hour | Description |
|---|---|---|---|---|---|---|---|---|
96564c9f |
Mar 6 | 29.7h | 1,254 | 30 | 820,563 | $671 | $22.59 | FIRST MOMENTS Wake-up protocol, identity formation |
d0d6d3fb |
Mar 7 | 37.9h | 1,078 | 53 | 1,195,254 | $975 | $25.72 | CIV PROJECT Telegram, portal, deep work |
1b14c79c |
Mar 9 | 15.1h | 572 | 33 | 541,924 | $483 | $32.00 | RECOVERY Cross-civ restart, Telegram reconnect |
efcd9667 |
Mar 10 | 34.0h | 1,427 | 59 | 1,397,293 | $1,028 | $30.25 | HEAVIEST Full workday: research, builds, web, agents |
360ceed6 |
Mar 11 | 0.5h | 41 | 0 | 6,175 | $10 | $20.84 | CRASH RECOVERY Quick restart handoff |
50d3927e |
Mar 11 | 25.1h | 244 | 26 | 399,936 | $361 | $14.39 | EFFICIENT Post-crash, focused agent work |
b2b1a45d |
Mar 12 | 5.3h | 295 | 16 | 211,658 | $182 | $34.21 | CURRENT Today's session (in progress) |
50d3927e on Mar 11 at $14.39/hr — focused work with fewer but deeper agent delegations. Most expensive per hour: b2b1a45d at $34.21/hr — high turn frequency during active use today.Based on deep analysis of the largest session (efcd9667, 1,427 turns). Each turn was classified by what tools were used.
| Activity Type | Turns | % of Session | Avg Cost/Turn | Total Est. Cost | Efficiency |
|---|---|---|---|---|---|
| Compact Resume Context compaction & continuation |
19 | 1.3% | $2.26 | $42.95 | MOST EXPENSIVE / TURN |
| Telegram Messages Processing TG messages from Joe |
72 | 5.0% | $0.84 | $60.23 | MODERATE |
| Web Research WebSearch + WebFetch operations |
46 | 3.2% | $0.68 | $31.40 | MODERATE |
| File Write/Edit Creating or modifying files |
187 | 13.1% | $0.53 | $99.41 | GOOD VALUE |
| Agent Spawn Delegating to subagents |
35 | 2.5% | $0.54 | $18.82 | GOOD VALUE |
| Bash Commands Running shell commands |
489 | 34.3% | $0.44 | $215.27 | EFFICIENT |
| File Read/Search Read, Grep, Glob operations |
357 | 25.0% | $0.39 | $138.32 | EFFICIENT |
| Pure Conversation Chat with no tools used |
202 | 14.2% | $0.09 | $18.78 | CHEAPEST |
| Component | Input Tokens | Output Tokens | Cache Read | Cache Create | Est. Cost |
|---|---|---|---|---|---|
| Primary (Conductor) | 108,051 | 2,169,642 | 858,413,630 | 31,163,617 | $2,036 |
| Subagents (all 217) | 822,149 | 2,399,709 | 390,243,101 | 48,635,650 | $1,690 |
Compaction (/compact) happens when context fills up. It summarizes the conversation and starts a continuation. This is expensive because it creates large new cache entries.
| Tool | Total Calls | % of All Tools | Cost Impact | Notes |
|---|---|---|---|---|
| Bash | 2,602 | 57.6% | LOW | Most frequent. Each call is cheap ($0.44/turn avg). Backbone of file ops, git, python. |
| Read | 665 | 14.7% | LOW | Reading files. Very efficient at $0.39/turn avg. |
| Edit | 364 | 8.1% | MODERATE | File modifications. Good value — creates actual deliverables. |
| Grep | 213 | 4.7% | LOW | Code search. Very efficient for finding information. |
| Write | 171 | 3.8% | MODERATE | Creating new files. Good value when creating HTML reports, configs. |
| Agent | 166 | 3.7% | HIGH | Spawning subagents. Each spawn creates a new context ($7.79 avg per agent lifecycle). |
| WebSearch | 92 | 2.0% | MODERATE | Web research. Multiple API calls per search turn (avg 2.7). |
| Glob | 82 | 1.8% | LOW | File pattern matching. Extremely efficient. |
| WebFetch | 60 | 1.3% | MODERATE | Fetching web pages. Content size varies — large pages cost more. |
| TaskUpdate/Create | 86 | 1.9% | LOW | Task management. Minimal token overhead. |
Every turn (message + response) reads the full cached context. A session with 100 turns costs roughly the same in cache reads regardless of whether each turn is 5 words or 500 words. Batch your instructions into fewer, richer messages.
5 turns = ~$2.00 in cache reads alone
1 turn = ~$0.40 in cache reads (but more output tokens)
| Instead of... | Try... | Savings |
|---|---|---|
| 5 separate "RAS [topic]" messages | One message: "RAS these 5 topics: [list]" | ~$1.60 in cache reads |
| "Check email" then "Reply to Joe's msg" then "Draft for KLJ" | "Check email. Reply to any from Joe with [X]. Draft response to KLJ about [Y]." | ~$0.80 |
| Sending corrections one at a time ("change this", "also fix that") | One message with all corrections listed | ~$0.40 per correction avoided |
| "What's the status?" then "Ok, do the next thing" | "Status check, then proceed with the next priority" | ~$0.40 |
| Operation | Est. Cost | Rating | Notes |
|---|---|---|---|
| Quick question / status check | $0.09 | CHEAP | Pure conversation, no tools. Best for "what's the status?" type queries. |
| File search (Grep/Glob/Read) | $0.39 | CHEAP | Finding and reading files. Very efficient. |
| Run a bash command | $0.44 | CHEAP | Shell operations, git, python scripts. |
| Edit/write a file | $0.53 | MODERATE | Good value — produces actual deliverables. |
| Spawn a subagent (simple task) | ~$3-5 | MODERATE | Short-lived agent for focused task. New cache creation adds cost. |
| Web research (search + fetch) | $0.68 | MODERATE | Multiple API calls. Fetched content increases context size. |
| Process a Telegram message | $0.84 | MODERATE | Includes routing, thinking, and often tool use. |
| Spawn a subagent (complex research) | ~$8-15 | EXPENSIVE | Long-running agent with web research, many files read. |
| Compaction (/compact) | $2.26 | EXPENSIVE | Rebuilds entire cache. Necessary but costly. Delay until 80% context. |
| Full wake-up protocol | ~$10-20 | EXPENSIVE | Reads constitutional docs, checks email, activates memory, intel scan. First 5 min of every session. |
| Multi-agent team lead session | ~$50-100+ | VERY EXPENSIVE | Team lead + multiple specialists. Highest output but highest cost. |
| Scenario | Efficient Phrasing | Why It's Better |
|---|---|---|
| Research task | "RAS [URL or topic]. Create HTML report at exports/[name].html with TPJG styling." | One turn: clear deliverable, clear format, clear location. |
| Multiple tasks | "Three things: (1) Check email and respond to client inquiries. (2) Update the LOC tracker with [data]. (3) Create a status summary." | Numbered list lets Tether batch all three in one session flow. |
| Corrections to a deliverable | "Update [file]: change X to Y, fix the table header, add a row for Z, and move section A above section B." | All corrections in one turn instead of 4 separate messages. |
| Exploratory question | "What's our current status on [X]? If there are blockers, suggest 3 solutions." | Pre-empts the follow-up question ("ok so what should we do?"). |
| File delivery | "Create [document], save to exports/, and provide the Netlify link." | Includes delivery instructions upfront — no follow-up needed. |
| Tier | Cost Range | Examples |
|---|---|---|
| MICRO | <$0.25 | Status checks, simple questions, "yes/no" confirmations |
| LIGHT | $0.25 – $1 | File reads, bash commands, single file edits, short Telegram replies |
| MEDIUM | $1 – $10 | Web research, single agent delegation, HTML report creation, email processing |
| HEAVY | $10 – $50 | Multi-agent research, full wake-up protocol, complex multi-step builds |
| INTENSIVE | $50+ | Team lead sessions with multiple specialists, full-day autonomous operation |
~/.claude/projects/-home-aiciv/ (73MB total)~/.claude/projects/-home-aiciv-civ/ (14MB)~/memories/sessions/| Metric | Source | Confidence |
|---|---|---|
| Token counts (input, output, cache) | Anthropic API usage data in JSONL | HIGH — direct from API responses |
| Tool call counts | Parsed from assistant message content blocks | HIGH — direct from message data |
| Session durations | First/last timestamp in each JSONL | GOOD — includes idle time |
| Dollar costs | Calculated from token counts x published Opus pricing | ESTIMATED — actual plan costs may differ significantly |
| Per-activity costs | Turn classification + average token usage | ESTIMATED — classification is heuristic-based |
| Savings projections | Extrapolated from patterns | ESTIMATED — rough projections, not guarantees |
| Model | Input (per MTok) | Output (per MTok) | Cache Read (per MTok) | Cache Create (per MTok) |
|---|---|---|---|---|
| Claude Opus 4 | $15.00 | $75.00 | $1.50 | $18.75 |
| Claude Sonnet 4 | $3.00 | $15.00 | $0.30 | $3.75 |