v18.4.0

A feature release. The brain format (version: 7) and the search cache format are unchanged; bf.yaml gains an optional prompts: section, which an older bf rejects, and the reply schemas only gain optional fields. Upgrade with uv tool upgrade brain-framework (or update a brain's pin), run bf skills DIR to update bf-maintain, which now covers prompts, and the retrieval guide, and copy the updated example hooks and weekly-review routine into your brain, preserving local adaptations.

Added

• Prompts run your agent harness over the brain, every 30 minutes by default or now with bf run PROMPT --stdin. Declare one under prompts: with a Markdown prompt file in prompts/ and a direct-argv command: BF expands {{brain}}, {{home}}, {{start}}, {{end}} and {{input}} in the file once, then passes it as the command's {{prompt}} argument or, without one, on standard input. BF never runs a model itself. Each successful run becomes a record in memories/NAME/ with the reply as its text (text selects it in JSON output, such as /response), its input, window, duration and the harness's other output, such as token usage, so later runs, bf search and your agents read it back; those records rank like a low-priority source, so a summary never outranks its evidence. See Run prompts.
• bf update runs due prompts after sensors and routines, outside the update lock; bf watch runs them in a second process beside collection, so a long agent run never delays a sensor, and marks them @ with their run counts. A direct run never waits for a scheduled one and leaves the schedule's history unchanged, failures included; a scheduled run checks again under its lock that no other process just ran it.
• bf update --kind sensor|routine|prompt, repeatable, keeps only those kinds of program; update, watch and schedule accept --prompt NAME selectors.
• The example session hook names failing or overdue prompts in its attention line, beside sensors and routines.
• bf status reports prompts with their state, freshness, runs, last run, latest record and failures; attention and the home page list failing or overdue prompts, and bf validate checks that each enabled prompt's file exists.

Changed

• bf run takes a routine or a prompt: its argument is named PROGRAM.
• A routine's {{prompt}} placeholder is invalid, as before; only a prompt's command takes it.
• CI and security workflows pin jdx/mise-action v5.1.1. The explicit mise 2026.10.0 pin keeps tool-manager upgrades deliberate; the action's 24-hour release-age default applies only without that pin.

Fixed

• Cancellation during sensor or routine startup now kills the newly created process group. Markdown complexity tests compare CPU-time growth, and cancellation tests wait for observed process termination, avoiding fixed-speed assumptions on slow CI runners.
• Period pages and search scopes place records without time by attributes.observed, including source counts and ordering across brains. Replies keep observation separate from event time; records with neither timestamp remain outside periods, and undated still selects every record without event time.
• The weekly-review example lists projects as plain bullets, with overdue reviews first and earliest deadlines first, and separates the open-task preview from its surrounding paragraphs. Generated reviews no longer create duplicate checkbox tasks; complete work in the owning notes.
• The session and prompt hooks keep nonempty stale cache results while collection runs, showing “Index refreshing”. They tolerate only the exact stale-cache identity problem; empty generations, malformed metadata and other problems stay silent.