Reference

TOML Filters

Boost compresses command output with Go parsers for major tools and declarative TOML filters for everything else. Drop a filters.toml file in your home config or project to teach Boost how to trim a custom script, linter, or internal CLI — no recompile required.

Where filters load

Boost merges filters from several locations. Later files can add new filters; the first match_command regex that matches the command line wins at runtime.

Built-in filters shipped with Boost (make, terraform, shellcheck, …)
~/.config/boost/filters.toml
.boost/filters.toml in your repo (commit this for team-wide rules)

Example: custom deploy script

Your team runs ./scripts/deploy.sh through Boost. The script prints hundreds of progress lines but only errors matter to the agent.

.boost/filters.toml

schema_version = 1

[filters.deploy]
description = "Keep failures from deploy.sh"
match_command = "^\\./scripts/deploy\\.sh\\b"
strip_ansi = true
keep_lines_matching = [
  "^(ERROR|WARN|FAIL)",
  "^\\s+at ",
]
max_lines = 80
on_empty = "deploy: ok"

Before (raw)

==> Resolving staging manifest…
==> Pulling image acme/web:staging
==> Waiting for rollout (1/3 ready)
==> Waiting for rollout (2/3 ready)
ERROR: pod api-7f9c failed readiness: connection refused
    at deploy.sh:142 check_health
WARN: retry 1/3 in 5s
==> Rollout complete

After Boost filter

ERROR: pod api-7f9c failed readiness: connection refused
    at deploy.sh:142 check_health
WARN: retry 1/3 in 5s

$ boost ./scripts/deploy.sh staging

Example: strip `make` chatter

Built-in filters use the same schema. This mirrors the shipped make filter: drop entering/leaving directory lines and blank rows.

[filters.make]
match_command = "^make\\b"
strip_lines_matching = [
  "^make\\[\\d+\\]:",
  "^\\s*$",
  "^Nothing to be done",
]
max_lines = 50
on_empty = "make: ok"

Before

make[1]: Entering directory '/home/user/app'
gcc -O2 -c src/main.c
gcc -O2 -o app src/main.o

make[1]: Leaving directory '/home/user/app'

After

gcc -O2 -c src/main.c
gcc -O2 -o app src/main.o

Example: short-circuit on clean lint

Use match_output to return a one-line summary when the tool succeeded quietly.

[filters.eslint-quiet]
match_command = "^eslint\\b"
match_output = [
  { pattern = "0 problems", message = "eslint: ok" },
]

Filter fields

Field	Purpose
match_command	Required regex against the full command line
strip_ansi	Remove terminal color codes first
strip_lines_matching	Drop lines matching any pattern
keep_lines_matching	Keep only matching lines
truncate_lines_at	Cap each line length
head_lines / tail_lines	Keep first or last N lines
max_lines	Total line budget with `...+N more lines` suffix
match_output	Replace entire output when a pattern matches
on_empty	Message when filtering removes everything

Commands without a Go or TOML filter pass output through unchanged. See the full reference in docs/TOML_FILTERS.md on GitHub.

Supported Commands

Browse the 121+ tools with dedicated Go filters.

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