What it is
Workflow tool's concurrent-agent limit can now be overridden with an environment variable
Not Anthropic's. This is the line from the earliest changelog entry here that named it, v2.1.269.
Presence across releases
1Build by build
11One row per release since the first build this name was read out of. Absent means the build was read and the name was not in it, never mined means no bundle for that release was ever archived, and a declared type or a default is only ever what that release's own bundle stated.
First cited
1The earliest release whose published evidence quoted CLAUDE_CODE_WORKFLOW_MAX_CONCURRENT_AGENTS was v2.1.269, 11 Sep 2026. That is the oldest release this project wrote about it, so it is a floor on the name's age and not the release that introduced it. It is not a presence reading: which builds carried the name is the table above.
Names beside it
Every environment variable in the inventory starting claude_code_workflow, up to twelve of them.
CLAUDE_CODE_WORKFLOW_PREFIX_STAGGER_MSParallel workflow agents stagger their first call to share cache; tune with an env var. v2.1.229
CLAUDE_CODE_WORKFLOW_PROMPT_PROVENANCEWorkflow runs now label whether a person or a schedule triggered them, and quote the request. never mined
CLAUDE_CODE_WORKFLOW_SIZE_WARNING_AGENTSNo description from anybody. v2.1.203
CLAUDE_CODE_WORKFLOW_SIZE_WARNING_TOKENSNo description from anybody. v2.1.203
CLAUDE_CODE_WORKFLOWSEnvironment flags are now parsed centrally, so values are compared to explicit true or false. v2.1.146
Read out of the published npm bundle release by release, and out of Anthropic's own documentation as this site captured it. Nothing on this page is a description anybody here wrote about what the environment variable does. All environment variables.