Context Diff

context-diff

**`git diff` for your Claude Code context window.** See exactly which tool call ate 40k tokens, which turn evicted the cache, and how close you are to hitting the 200k ceiling.

[](https://pypi.org/project/context-diff/) []() []()

---

Why

Your Claude Code session keeps hitting "auto-compact triggered." You suspect some tool result is huge — but which? Was it the 80-file `find`, the `Read` on the giant log, or the third agent you spawned in parallel?

`context-diff` reads your session JSONL (Claude Code records every turn locally) and renders a turn-by-turn token waterfall: input tokens, cache reads, deltas, which tool calls fired, and the top-N biggest jumps.

You go from "my context is full and I don't know why" to "Turn 14's `Grep` returned 38k tokens — I should have piped it through `head`" in 2 seconds.

---

Install

pip install context-diff
# or
uvx context-diff --auto

Zero dependencies. Pure Python ≥3.10.

---

Use

# Auto-pick the most recently modified session
context-diff --auto

# Or point at a specific session
context-diff ~/.claude/projects/-Users-you-proj/abc-def.jsonl

# Show top 10 biggest turns
context-diff --auto --top 10

# Machine-readable
context-diff --auto --json | jq '.[] | select(.delta_input > 10000)'

---

Example output

Turn  Kind          Δ tokens         in   cache_r  Label
─────────────────────────────────────────────────────────────────
   1  user                 —          —         —  user: fix the auth bug in /login
   2  assistant        1.2k        1.2k         —  ⬆ Read, Grep
   3  tool_result          —          —         —  ↳ tool_result × 2  (8,420 chars)
   4  assistant        2.1k        850       1.2k  ⬆ Edit
   5  tool_result          —          —         —  ↳ tool_result × 1  (320 char