docs: split bitlesson workflow into dedicated guide

Author: zenus

README.md

@@ -68,7 +68,7 @@ Requires [codex CLI](https://github.com/openai/codex) for review. See the full [
 - [Install for Codex](docs/install-for-codex.md) -- Codex skill runtime setup
 - [Install for Kimi](docs/install-for-kimi.md) -- Kimi CLI skill setup
 - [Configuration](docs/usage.md#configuration) -- Shared config hierarchy and override rules
-- [Bitter Lesson Workflow](docs/usage.md#bitlesson-workflow) -- Project memory, selector routing, and delta validation
+- [Bitter Lesson Workflow](docs/bitlesson.md) -- Project memory, selector routing, and delta validation
 
 ## License
 

docs/bitlesson.md

@@ -0,0 +1,47 @@
+# Bitter Lesson Workflow
+
+BitLesson is the repository's Bitter Lesson-style knowledge capture system for RLCR rounds.
+
+## Configuration
+
+The selector reads `bitlesson_model` from the merged config hierarchy:
+
+1. `config/default_config.json`
+2. `~/.config/humanize/config.json`
+3. `.humanize/config.json`
+4. CLI flags where applicable
+
+Provider routing is automatic:
+
+- `gpt-*`, `o1-*`, `o3-*` route to Codex
+- `claude-*`, `haiku`, `sonnet`, `opus` route to Claude
+
+If the configured provider binary is missing, the selector falls back to the default Codex model so the loop can still proceed.
+
+## Workflow
+
+Each project keeps its BitLesson knowledge base at `.humanize/bitlesson.md`.
+
+When `start-rlcr-loop` begins:
+
+1. The file is initialized from `templates/bitlesson.md` if it does not already exist
+2. Each task or sub-task runs through `scripts/bitlesson-select.sh`
+3. The selected lesson IDs are applied during implementation, or `NONE` is recorded when nothing matches
+4. The stop gate validates a required `## BitLesson Delta` section in every round summary
+
+## Summary Contract
+
+Required summary shape:
+
+```markdown
+## BitLesson Delta
+- Action: none|add|update
+- Lesson ID(s): <IDs or NONE>
+- Notes: <what changed and why>
+```
+
+Validation rules are strict:
+
+- `Action: none` must use `Lesson ID(s): NONE` or leave the field empty
+- `Action: add` and `Action: update` must reference concrete `BL-YYYYMMDD-short-name` IDs that exist in `.humanize/bitlesson.md`
+- `--require-bitlesson-entry-for-none` can be used to block empty knowledge bases from repeatedly reporting `none`

docs/usage.md

@@ -180,42 +180,8 @@ Codex model is resolved with this precedence:
 `loop_reviewer_model` or `loop_reviewer_effort`, they are silently ignored.
 Use `codex_model` and `codex_effort` instead.
 
-### BitLesson Configuration
-
-BitLesson is the repository's Bitter Lesson-style knowledge capture system for RLCR rounds.
-
-The selector reads `bitlesson_model` from the merged config. Provider routing is automatic:
-
-- `gpt-*`, `o1-*`, `o3-*` route to Codex
-- `claude-*`, `haiku`, `sonnet`, `opus` route to Claude
-
-If the configured provider binary is missing, the selector falls back to the default Codex model so the loop can still proceed.
-
-## BitLesson Workflow
-
-Each project keeps its BitLesson knowledge base at `.humanize/bitlesson.md`.
-
-When `start-rlcr-loop` begins:
-
-1. The file is initialized from `templates/bitlesson.md` if it does not already exist
-2. Each task or sub-task runs through `scripts/bitlesson-select.sh`
-3. The selected lesson IDs are applied during implementation, or `NONE` is recorded when nothing matches
-4. The stop gate validates a required `## BitLesson Delta` section in every round summary
-
-Required summary shape:
-
-```markdown
-## BitLesson Delta
-- Action: none|add|update
-- Lesson ID(s): <IDs or NONE>
-- Notes: <what changed and why>
-```
-
-Validation rules are strict:
-
-- `Action: none` must use `Lesson ID(s): NONE` or leave the field empty
-- `Action: add` and `Action: update` must reference concrete `BL-YYYYMMDD-short-name` IDs that exist in `.humanize/bitlesson.md`
-- `--require-bitlesson-entry-for-none` can be used to block empty knowledge bases from repeatedly reporting `none`
+For BitLesson-specific configuration, workflow rules, and summary validation, see
+[Bitter Lesson Workflow](bitlesson.md).
 
 ## Monitoring