or as the first step in a stacked pipeline, usually:

rtk -> caveman

command-output savings. Its README sample session goes from standard tokens to RTK tokens, which is saved (). OmniRoute uses that upstream average for the stacked savings calculation with Caveman input compression:

RTK average:    80% saved
Caveman input: 46% saved
Stacked:       1 - (1 - 0.80) * (1 - 0.46) = 89.2% saved
Range:         1 - (1 - 0.60..0.90) * (1 - 0.46) = 78.4-94.6%

	, , ,
	, , , , Poetry, Bundler
	, , , generic shell logs
	, Docker logs

classifies output before filter selection. Filters can also match by command pattern or output regex when a command class is not enough.

, only when trusted.
1. .
2. .

is .
• is set.
• contains the SHA-256 hash of .

{
  "filtersSha256": "0123456789abcdef..."
}

diagnostics. Invalid built-in filters fail fast.

Compression Rules Format. The runtime applies these stages in order:

stripAnsi -> filterStderr -> replace -> matchOutput -> drop/include lines
  -> truncateLineAt -> head/tail/maxLines -> onEmpty

samples. Custom filters should include them too, especially when they are shared across projects.

. RTK-specific settings are also available through .

{
  "defaultMode": "stacked",
  "autoTriggerMode": "stacked",
  "autoTriggerTokens": 32000,
  "stackedPipeline": [
    { "engine": "rtk", "intensity": "standard" },
    { "engine": "caveman", "intensity": "full" }
  ],
  "rtkConfig": {
    "enabled": true,
    "intensity": "standard",
    "applyToToolResults": true,
    "applyToCodeBlocks": false,
    "applyToAssistantMessages": false,
    "enabledFilters": [],
    "disabledFilters": [],
    "maxLinesPerResult": 120,
    "maxCharsPerResult": 12000,
    "deduplicateThreshold": 3,
    "customFiltersEnabled": true,
    "trustProjectFilters": false,
    "rawOutputRetention": "never",
    "rawOutputMaxBytes": 1048576
  }
}

and use filter ids, for example or .

{
  "command": "npm test",
  "text": "FAIL tests/example.test.ts\nAssertionError: expected true\nTest Files 1 failed",
  "config": {
    "intensity": "standard"
  }
}

{
  "mode": "stacked",
  "messages": [
    {
      "role": "tool",
      "content": "FAIL tests/example.test.ts\nAssertionError: expected true\nTest Files 1 failed"
    }
  ],
  "config": {
    "rtkConfig": {
      "rawOutputRetention": "failures"
    }
  }
}

can retain redacted raw output:

DATA_DIR/rtk/raw-output/

, , values. Analytics stores only the pointer id, size, and hash metadata.

node --import tsx/esm --test tests/unit/compression/rtk-verify.test.ts

node --import tsx/esm --test \
  tests/unit/compression/rtk-*.test.ts \
  tests/unit/compression/pipeline-integration.test.ts \
  tests/unit/compression/context-compression-api.test.ts

node --import tsx/esm --test \
  tests/unit/compression/*.test.ts \
  tests/golden-set/*.test.ts \
  tests/integration/compression-pipeline.test.ts \
  tests/unit/api/compression/compression-api.test.ts

1. sample that proves the important behavior.
2. for new command families.
5. and refresh only after review.