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+# Decisions
+
+Rules the maintainers settled, numbered in order. Triage designs and code reviews check
+every change against the entries whose "Applies to" it touches. Change a rule by adding an
+entry that supersedes it, never by editing an old one.
+
+## D-1: Read runs and replaced proposals have their own decision status
+
+- Decided: 2026-10-09, in cloudfall-dev/cloudfall#26
+- Rule: A decision for a risk: read operation is recorded as status ran with the check run's exit code, and a newer proposal of the same operation, targets and inputs marks the older proposed record superseded with superseded_by naming the new decision; the existing status values keep their single meaning
+- Why: A read run is finished when recorded and a repeated proposal replaces the old one; reusing executed or rejected would give one status two meanings in the record
+- Applies to: sdk/src/cloudfall/decision.py, config/schemas/v1/operation-decision.schema.json, decisions list, cloudfall why
+- Enforced by: review
+
+## D-2: A replayed decision is marked and cannot be approved
+
+- Decided: 2026-10-09, in cloudfall-dev/cloudfall#36
+- Rule: A decision proposed during agent investigate --replay carries a replay field naming the recording, decisions approve refuses it with PRECONDITION, and --replay refuses a --decisions folder that is the recording itself
+- Why: Its check output was played back, not run on the host, so approving it would let the gate trust evidence that never came from the host
+- Applies to: sdk/src/cloudfall/app.py, sdk/src/cloudfall/decision.py, sdk/src/cloudfall/recording.py, config/schemas/v1/operation-decision.schema.json, decisions approve
+- Enforced by: review
+
+## D-3: A run cut short is recorded as stopped
+
+- Decided: 2026-10-09, in cloudfall-dev/cloudfall#44
+- Rule: When agent investigate cannot finish because its reader went away, the investigation record is saved with status stopped and the command exits non-zero
+- Why: A record saved with the status it had mid-run looks like a run still going or one that ended normally
+- Applies to: sdk/src/cloudfall/investigation.py, sdk/src/cloudfall/app.py, config/schemas/v1/agent-investigation.schema.json, agent investigate
+- Enforced by: review
+
+## D-4: Model reasoning in the investigation record is capped
+
+- Decided: 2026-10-09, in cloudfall-dev/cloudfall#50
+- Rule: The investigation record keeps at most 8000 characters of a turn's reasoning in spec.trace, like TOOL_TEXT_LIMIT, and marks the cut; the schema bounds the field
+- Why: The model's reasoning quotes host output it read, so unbounded reasoning makes the record unbounded and stores host output in it
+- Applies to: sdk/src/cloudfall/investigation.py, config/schemas/v1/agent-investigation.schema.json
+- Enforced by: review