30-second demo · click to play · or see docs/demo.cast in this repo
What is Excise?
Anthropic's own documentation observes that more than two corrections in a
single Claude Code session reliably poisons the trajectory — the agent starts
fighting ghosts of the cut-off path you abandoned. The fix today is
/clear (lose all context) or /compact (lose nuance). Excise is the
missing third option: a single-binary CLI that opens an interactive picker
over the session JSONL on disk, lets you cut the three turns that took the
agent down the dead end, and writes the file back with snapshot-and-undo
safety.
before after
┌──────────────┐ ┌──────────────┐
│ user │ │ user │
│ assistant │ │ assistant │
│ user │ ─▶ │ (excised) │
│ assistant ✗ │ │ (excised) │
│ user │ │ user │
│ assistant ✓ │ │ assistant ✓ │
└──────────────┘ └──────────────┘
The primitive Excise(Session, set<turn_id>) -> Session' preserves four
invariants: (1) removing a tool_use turn also removes its paired
tool_result, (2) removing a tool_result warns about the surviving
owner, (3) ordering and stable ids are preserved, (4) writes are
atomic (snapshot, write-to-tmp, rename).
# via go
go install github.com/SuperMarioYL/excise/cmd/excise@latest
# via homebrew (after the tap is published — see BUILD_SETUP_NEXT_STEPS.md)
brew install supermarioyl/tap/excise
# from source
git clone https://github.com/SuperMarioYL/excise && cd excise
go build -o ./excise ./cmd/excise
Excise ships as a single ~8 MB static binary. No runtime, no daemon, no
network call.
Quick start
# Zero-arg: auto-discover the newest Claude Code session and open the picker
excise
# Render the turn table, no edits
excise list
# Open the picker on a specific session file
excise pick ~/.claude/projects/-home-me-app/SESSION-UUID.jsonl
# Non-interactive cut: remove turns 5-7 and 9
excise cut 5-7,9 ~/.claude/projects/-home-me-app/SESSION-UUID.jsonl
# Same, but for a Cursor session
excise --tool=cursor cut 12-14 "~/Library/Application Support/Cursor/User/globalStorage/state.vscdb"
# Restore the most recent snapshot
excise rollback --list
excise rollback <snapshot-id>
In the TUI:
key
action
j / ↓
move down
k / ↑
move up
g / G
jump to top / bottom
space / x
toggle mark on current turn
d
mark + move down
enter
commit the cut
q / ctrl+c
abort without changes
The header live-updates turns: 42 → 39 tokens: ~18.2k → ~12.4k as you mark.
v0.2 — Suggestions
excise suggest runs a pure-stdlib heuristic scorer over the session and
nominates the top-K candidate turns to excise. Zero network, no LLM, no
auto-cut — the scorer only suggests; you still confirm in the TUI.
# role tokens heuristic preview
--- --------- ------ ---------------------------------------------- ----------------------
17 assistant 2840 high_token_cost + user_correction_follows_up "Let me try refactoring …"
19 tool_use 420 tool_use_error_then_correction Edit(path=foo, …) ERROR
32 assistant 3100 high_token_cost + repeated_file_edit "Actually let me revert …"
33 assistant 1820 repeated_file_edit + user_correction_follows_up "I'll switch to using …"
47 assistant 2200 long_drift_no_tool_calls + high_token_cost "To summarize what we …"
5 candidates totalling ~10,380 tokens. Run `excise pick` to review interactively.
Five heuristics contribute to each turn's score:
trigger
what it fires on
high_token_cost
assistant or tool turn weighing ≥ 2 000 tokens
repeated_file_edit
same file edited 3+ times in a row (window = 3)
user_correction_follows_up
next user turn matches the bilingual correction lexicon (no, actually, try a different approach, 不对, 换个思路 …)
tool_use_error_then_correction
a tool returned an error AND the next user turn said so
long_drift_no_tool_calls
5+ consecutive assistant turns with no tool_use
excise pick calls the scorer by default and pre-marks the top-K
candidates in the TUI — those marks render with a [◆] glyph instead of
the manual [x]. Toggle freely with space; commit only honors your final
marks. Pass --no-suggest to restore v0.1 behavior.
# Dry-run the suggestion engine — never touches the file
excise suggest
# Top-3, only above score 1.5, JSON output
excise suggest --top=3 --min-score=1.5 --json testdata/claude_session_polluted.jsonl
# Skip the pre-mark — v0.1 picker behavior
excise pick --no-suggest
The scorer is a pure function of one session: no cross-session learning,
no acceptance log written, no shared cache. That keeps the trust premise
intact and means a v0.2 binary on an air-gapped machine behaves identically
to one online.
v0.3 — LLM rerank (opt-in, local Ollama)
v0.3 lets you optionally layer a local Ollama model on top of the v0.2
heuristic shortlist. The heuristic stays the cheap pre-filter; the LLM only
judges that shortlist and writes a one-line reason per turn. Default behaviour
is unchanged from v0.2 — --llm is the only switch.
# install ollama (https://ollama.com), then pull a small model:
ollama pull llama3.2
# point excise at it, just for this run:
excise suggest --llm session.jsonl
excise pick --llm session.jsonl # TUI shows the LLM reason next to each pre-marked turn
Optional excise.toml (discovered at ./excise.toml → $XDG_CONFIG_HOME/excise/excise.toml
→ ~/.config/excise/excise.toml):
[llm]
host = "http://localhost:11434" # your Ollama
model = "llama3.2"
top_n = 5
timeout_sec = 20
Graceful fallback. If Ollama is unreachable, the model is missing, the call
times out, or the response is malformed, Excise prints one line to stderr —
[excise] LLM unavailable (<reason>) — falling back to heuristic ranking
— and continues with the v0.2 heuristic result. You always get some output;
--llm set in muscle memory never hard-blocks you.
Trust contract under --llm (unchanged from v0.1/v0.2):
No outbound network beyond the host you configured. Default
http://localhost:11434 is your own Ollama; if you point elsewhere you made
that choice explicitly.
No autocut.--llm only changes the ranking — every excision is still
user-confirmed in the TUI or via explicit excise cut <range>.
No telemetry, no acceptance log, no cross-session learning. Same posture
as v0.1/v0.2.
Remote API-key backends (OpenAI / Anthropic / OpenRouter) are deferred to v0.4.
Commands
excise [path] open the TUI (auto-discover if no path; pre-mark via heuristics)
excise list [path] print the turn table (no edits)
excise pick [path] open the TUI (alias for the bare command)
excise cut <range> [path] non-interactive; e.g. "5-7,9"
excise suggest [path] v0.2 — print top-K heuristic candidates (read-only)
excise rollback --list list every snapshot, newest first
excise rollback <snapshot-id> restore one snapshot
global flags:
--tool auto|claude|cursor transcript format (default: auto)
--session PATH explicit session path
--force proceed despite dependency warnings
--dry-run show the diff but do not write
-y, --yes skip the confirmation prompt
--no-suggest v0.2 — skip the heuristic pre-mark in the picker
--llm v0.3 — rerank the heuristic shortlist via local Ollama
--llm-model NAME v0.3 — override model from excise.toml (e.g. llama3.2)
--llm-host URL v0.3 — override host from excise.toml
suggest-only flags:
--top N show at most N suggestions (0 = all; default 5)
--min-score X drop suggestions below score X (default 0)
--json emit JSON instead of a table
How dependency-aware cutting works
A Claude Code (or Cursor) turn that issues a tool call creates a downstream
tool_result turn. If you cut the tool call but leave its result behind, the
agent's next turn references a tool_use_id that no longer exists and the
model gets confused.
Excise builds a dependency graph from every tool_use.id ↔ tool_result.tool_use_id
edge, computes the transitive closure of your marked set, and (a) pulls every
dependent result into the cut automatically (invariant 1), and (b) warns when
your selection would orphan a tool_result whose owner survives (invariant 2).
Pass --force to override the warning.
and appends a JSON line to ~/.excise/edit_log.jsonl recording what was
removed, when, and why. Snapshots older than 30 days are auto-pruned on the
next commit so the directory stays bounded.
excise rollback <snapshot-id> restores byte-for-byte. The original
destination is read from the edit log; override with --to <path> if you
moved the session file.
side-car .excised.jsonl to avoid corrupting an open db
Cursor (fixture export)
*.jsonl of {"composerId":...,"bubble":{...}} lines
yes
atomic rewrite
sqlite3 is required only for the Cursor sqlite branch. macOS ships it; on
Linux: apt install sqlite3. The Cursor writer deliberately refuses to mutate
state.vscdb while Cursor is running — v0.2 will add a "Cursor must be
closed" guard and a direct write path.
Architecture
A polluted session on disk (Claude .jsonl or Cursor state.vscdb) is read by the session layer, which auto-detects the format and builds the tool_use ↔ tool_result dependency graph. The suggest pipeline scores every turn with five pure-stdlib heuristics — and, only when you pass --llm, reranks the shortlist through a local Ollama model. Candidates are pre-marked in the TUI picker where you confirm the cut; safety then snapshots the file (gzip), rewrites it atomically, and keeps a rollback path. Everything runs in one static binary — no daemon, no network.
v0.3 — direct state.vscdb writes with a "Cursor closed?" guard; opt-in
LLM-assisted suggestions as a plugin (local Ollama / user-supplied API key).
v0.4 — Codex / Aider / Cline support behind the same primitive.
v0.5 — excise grep <regex> to mark by content match.
v0.6 — a "session debugger" sidecar that lets you inspect tool-call
graphs without cutting anything.
Out of scope (on purpose)
Web UI or hosted service. CLI/TUI only.
Auto-cutting turns. v0.2 only suggests (pure-stdlib heuristics,
zero network); you still press enter to commit. excise autocut is
explicitly never going to ship.
LLM-assisted suggestions of any kind (local Ollama / user-supplied API
key / hosted endpoint). All deferred to v0.3 as opt-in plugins so the
v0.2 binary signature and trust premise stay put.
Prompt-cache reconciliation. Editing invalidates the cache; you accept the
cost.
A Claude Code plugin. We operate on the on-disk file between sessions.
Cloud sync, account system, team features.
Cross-tool session portability — that is cli-continues'
niche, not ours.
Telemetry of any kind, including opt-in.
Every refusal above keeps the demo under 30 seconds.
Contributing
Bug reports and PRs welcome. Please run go test -race ./... before
submitting. The hot path you most likely want to change is
internal/session/claude.go (schema tolerance) or internal/safety/backup.go
(snapshot policy). Anything bigger, open an issue first so we can agree on
scope.
Package safety implements the snapshot, edit-log, and rollback machinery that turns Excise from a "hope you backed up" knife into a "git for your agent transcript" pair of operations.
Package safety implements the snapshot, edit-log, and rollback machinery that turns Excise from a "hope you backed up" knife into a "git for your agent transcript" pair of operations.