Environment variables

Every variable uses the BEC_ prefix. Set them on the process that starts Claude Code or Codex.

Value formats:

Booleans read 1, true, yes, and on as true, and 0, false, no, off, and the empty string as false, case-insensitive. A value outside those two sets leaves the key alone.
Id lists are comma-separated and trimmed.
Path lists split on the platform path delimiter (: on Linux and macOS, ; on Windows).
A BEC_ALLOW_* or BEC_BYPASS_* value that starts with [ is parsed as a JSON array, and any other value as a comma list.

The layer column refers to the 5 config layers in configuration.md. Layer 2 sits under the BEC_CONFIG_PATH file, the user file, and the project file. Layer 5 sits over all three.

Variable	Value	Effect	Layer
`BEC_CONFIG_JSON`	JSON object	a whole config layer	2
`BEC_CONFIG_PATH`	path	a config file read under the user file and the project file; a relative path resolves against the cwd	3
`BEC_CONFIG_PATH_ONLY`	boolean	skips the user file and the project file, so only the `BEC_CONFIG_PATH` file applies	3, 4
`BEC_FEATURE_ENABLE`	id list	turns features and checks on	2
`BEC_FEATURE_DISABLE`	id list	turns features and checks off	2
`BEC_FEATURE_ALWAYS_ENABLE`	id list	turns features and checks on over the config files	5
`BEC_FEATURE_ALWAYS_DISABLE`	id list	turns features and checks off over the config files	5
`BEC_ENABLE_PATTERNS`	id list	adds to `features.aiWriting.enablePatterns`	2
`BEC_DISABLE_PATTERNS`	id list	adds to `features.aiWriting.disablePatterns`	2
`BEC_ALWAYS_ENABLE_PATTERNS`	id list	the same key, over the config files	5
`BEC_ALWAYS_DISABLE_PATTERNS`	id list	the same key, over the config files	5
`BEC_LOAD_LIB_PATHS`	path list	appended to `features.aiWriting.packs`	2
`BEC_HOOK_SOFT_FAIL`	boolean	`softFail`	5
`BEC_DISABLE_STOP_HOOK`	boolean	`stopHook`, inverted	5
`BEC_LOG_ENABLED`	boolean	`log.enabled`	5
`BEC_LOG_PATH`	path	`log.path`	5
`BEC_LOG_MAX_SIZE`	bytes, or a `k`, `m`, `g` suffix	`log.maxSize`	5
`BEC_LOG_MAX_FILES`	positive integer	`log.maxFiles`	5
`BEC_LOG_ROTATE`	`size`, `daily`, or `both`	`log.rotate`	5
`BEC_LOG_USE_JSON`	boolean	`log.format` as `json`	5
`BEC_LOG_USE_PLAINTEXT`	boolean	`log.format` as `plaintext`, which wins over `BEC_LOG_USE_JSON`	5
`BEC_MONITOR_PERSIST`	boolean	`monitor.persist`	5
`BEC_MONITOR_DISABLED`	`1`	skips the project registry, the record file, and the console feed	none
`BEC_ALLOW_PHRASES`	phrase list	`allowList.phrases`	5
`BEC_ALLOW_PATTERNS`	regex list	`allowList.patterns`	5
`BEC_BYPASS_PHRASES`	phrase list	`bypass.phrases`	5
`BEC_BYPASS_PATTERNS`	regex list	`bypass.patterns`	5

Feature ids for BEC_FEATURE_*: emDash, aiWriting, dictionary, comments, fileSize, prBody, stopHook, and the scan switches codeFiles, notebooks, heredocWrites, shellWrites, mcp, plans, tasks, and questions.

Pattern ids for BEC_*_PATTERNS: a category id, a pack id, or tag:<tag>. An unknown id is ignored. The category ids are listed in categories.md.

Scenario 1: a cloud agent with no config file

A cloud agent checks the repo out fresh and writes no config file. Set the whole configuration in the environment.

export BEC_FEATURE_ENABLE=emDash,aiWriting
export BEC_ENABLE_PATTERNS=file-narration,benefit-tail
export BEC_HOOK_SOFT_FAIL=1
export BEC_LOG_ENABLED=1

After those 4 lines, the dash check and the AI writing check run under the default preset, file-narration and benefit-tail run on top of it, every deny comes back as an allow prefixed [concise] soft-fail:, and one record per hook call lands in ~/.cache/concise/concise.log.

Set preset from the environment with BEC_CONFIG_JSON:

export BEC_CONFIG_JSON='{"features":{"aiWriting":{"enabled":true,"preset":"technical"}}}'

Scenario 2: force one category off over the project file

The project file sets "preset": "ryan", which turns on formatting. A repo that prefixes commit subjects with a gitmoji trips it on every commit. Turn that one category off for your sessions.

BEC_ALWAYS_DISABLE_PATTERNS=formatting claude

BEC_DISABLE_PATTERNS sits at layer 2, under the project file, so a project file that lists formatting in categories would win. BEC_ALWAYS_DISABLE_PATTERNS sits at layer 5, over the project file, and takes the category off in both cases.

The feature form works the same way. BEC_FEATURE_ALWAYS_DISABLE=aiWriting turns the whole AI writing check off over a project file that enables it.

Scenario 3: turn logging on for one session

BEC_LOG_ENABLED=1 BEC_LOG_PATH=/tmp/concise.log BEC_LOG_USE_PLAINTEXT=1 claude

Each hook call appends one line of ts hook tool decision key summary to /tmp/concise.log, with - for an empty cell. Read the denials with:

grep ' deny ' /tmp/concise.log

To keep the default JSON records and rotate them daily instead:

BEC_LOG_ENABLED=1 BEC_LOG_ROTATE=daily BEC_LOG_MAX_FILES=7 claude

That writes ~/.cache/concise/concise.YYYY-MM-DD.log and keeps 7 of them.