CLI Denoiser

Strip terminal noise for LLM agents. Zero false positives.

CLI Denoiser is a Rust-powered filter proxy that removes terminal noise from command output before it reaches your LLM agent. It saves tokens, reduces context pollution, and guarantees zero false positives -- signal always passes through.

Built for Claude Code, Codex CLI, Gemini CLI, and any agentic coding workflow.

Benchmark Results

Overall Performance

Metric	Value
Overall Savings	58.5%
Tokens Saved	912 across 11 scenarios
Avg Latency	~1.5ms per filter pass
False Positives	ZERO

Scenario Deep Dives

Full Benchmark Results

Scenario	Original	Filtered	Saved	Savings	Signal
cargo build (69 crates)	231	17	214	92.6%	OK
git clone (verbose)	85	8	77	90.6%	OK
docker pull (layer progress)	116	23	93	80.2%	OK
npm install (deprecation spam)	249	63	186	74.7%	OK
mixed ANSI + progress	101	41	60	59.4%	OK
kubectl events (scheduling noise)	162	69	93	57.4%	OK
git push (transfer stats)	166	77	89	53.6%	OK
docker build (cached layers)	189	103	86	45.5%	OK
cargo test (with failures)	170	158	12	7.1%	OK
pure signal (no noise)	70	68	2	2.9%	OK
npm install (clean, no warnings)	19	19	0	0.0%	OK

Signal column: every scenario has required signal strings that must appear in filtered output. OK means zero information was lost. The benchmark catches false positives automatically.

How It Works

CLI Denoiser runs a two-pass filter pipeline:

Line-level filtering -- each line is classified as Keep, Drop, Replace, or Uncertain. If any filter returns Uncertain, the line passes through (zero false positive guarantee baked into the type system).
Block-level collapsing -- consecutive noise lines are collapsed into summaries:
- Compiling serde v1.0.228 x47 lines becomes [compiled 47 crates]
- Per-layer Docker pull progress becomes [pulled 12 layers]
- Repeated deprecation warnings become [8 deprecation warnings]

What Gets Filtered

Filter	Strips	Preserves
ANSI	CSI sequences, OSC, color codes, carriage returns	All text content
Progress	Progress bars, Unicode spinners, percentage indicators	Final state
Dedup	3+ consecutive identical lines	First occurrence + count
Git	Transfer stats (Enumerating/Counting/Compressing objects)	Branch names, errors, diffs, status
npm	Timing logs, HTTP fetch, deprecation spam, peer dep warnings	Installed packages, errors, audit
Cargo	Compiling/Checking/Fresh/Downloading per-crate lines	Errors, warnings, test results, Finished summary
Docker	Layer cache, pull progress, digest lines, intermediate containers	Build steps, errors, final image ID
Kubectl	klog verbose output, routine scheduling events	Pod status, errors, custom resources
Generic	Decorative border lines (box-drawing characters)	Everything else (maximally conservative)

Install

From crates.io (recommended)

cargo install cli-denoiser

From GitHub releases

Download the latest binary for your platform from Releases, extract, and add to your PATH:

# macOS (Apple Silicon)
curl -L https://github.com/Orellius/cli-denoiser/releases/latest/download/cli-denoiser-aarch64-apple-darwin.tar.gz | tar xz
sudo mv cli-denoiser /usr/local/bin/

# macOS (Intel)
curl -L https://github.com/Orellius/cli-denoiser/releases/latest/download/cli-denoiser-x86_64-apple-darwin.tar.gz | tar xz
sudo mv cli-denoiser /usr/local/bin/

# Linux (x86_64)
curl -L https://github.com/Orellius/cli-denoiser/releases/latest/download/cli-denoiser-x86_64-unknown-linux-gnu.tar.gz | tar xz
sudo mv cli-denoiser /usr/local/bin/

From source

git clone https://github.com/Orellius/cli-denoiser.git
cd cli-denoiser
cargo install --path .

Setup hooks (one command)

cli-denoiser install

This auto-detects and configures hooks for:

Claude Code -- PostToolUse hooks on Bash, Read, and Grep tools
Codex CLI -- post_exec hook on shell tool
Gemini CLI -- post_tool_use hook on shell and bash tools

To remove:

cli-denoiser uninstall

Usage

As a command wrapper

# Wrap any command -- output is filtered automatically
cli-denoiser cargo build
cli-denoiser npm install
cli-denoiser docker build .
cli-denoiser git push origin main

As a pipe filter

# Pipe any output through the filter
cargo build 2>&1 | cli-denoiser filter --command cargo
kubectl get events | cli-denoiser filter --command kubectl

As an agent hook (recommended)

# Install hooks for all detected agents
cli-denoiser install

# That's it -- hooks run automatically on every tool call

View savings

cli-denoiser gain           # Last 30 days
cli-denoiser gain --days 7  # Last 7 days

Run benchmarks

cli-denoiser bench                              # Print to terminal
cli-denoiser bench --output bench-results.json  # Export JSON

Architecture

stdin/command
     |
     v
 +-------------------+
 | ANSI Filter       |  Strip escape codes (always first)
 +-------------------+
     |
     v
 +-------------------+
 | Progress Filter   |  Collapse progress bars and spinners
 +-------------------+
     |
     v
 +-------------------+
 | Dedup Filter      |  Collapse repeated lines (3+ threshold)
 +-------------------+
     |
     v
 +-------------------+
 | Command Filter    |  Git / npm / Cargo / Docker / Kubectl / Generic
 +-------------------+
     |
     v
  filtered output

Universal filters (ANSI, Progress, Dedup) run on every command. The command-specific filter is selected based on the binary name via CommandKind::detect().

Zero False Positive Guarantee

The type system enforces this:

pub enum FilterResult {
    Keep,                    // Definitely signal
    Drop,                    // Definitely noise
    Replace(String),         // Noise, but summarize
    Uncertain,               // Not sure -- ALWAYS passes through
}

When a filter returns Uncertain, the pipeline keeps the original line unchanged. There is no "aggressive mode" that might lose signal. The benchmark suite verifies this automatically: every scenario has required signal strings that must appear in filtered output.

Development

# Run all 4 verification gates
cargo clippy -- -D warnings
cargo test
cargo fmt --check
cargo check

# Build release binary
cargo build --release

License

Apache-2.0. See LICENSE.

cli-denoiser 0.1.1