Session State

HARD GATE — HARD GATE — Session state must be synchronized with git state. If state.yaml conflicts with the working tree, halt and ask for clarification. Do NOT assume state is correct.

Track the current state of implementation, including decisions made, pending tasks, and open questions, to ensure continuity across session boundaries and prevent "context rot."

Session-state implements the isolate strategy from the context-engineering framework (docs/references/context-engineering.md): each agent gets exactly the context it needs — no more — by recording decisions so the next agent can cold-start without replaying history. The four strategies (write, select, compress, isolate) work together: session-state handles isolation, terse-mode handles compression, survey-context handles selection, and CONVENTIONS.md ensures token-efficient writing.

Goal

Maintain a single source of truth for the current session in specs/state.yaml. This complements long-term docs in specs/tech-architecture/ and delivery detail in specs/epics/ + specs/release-plan.yaml.

Legacy markdown (specs/archive/STATE.md, RELEASE-PLAN.md) is not SoT when YAML exists — use specs/state.yaml only.

When a story modifies existing behavior, patch only between matching marker pairs in CLAUDE.md / AGENTS.md learned-preferences fence — see e45s21.

Handoff block (cold start)

When ending a session or before a context-heavy spawn, update handoff in state.yaml:

handoff:
  last_step_completed: "e02s01 verify-work passed"
  open_decisions:
    - "Use folder mode for e07 (>5 stories)"
  required_reading:
    - CONVENTIONS.md
    - specs/epics/e02-verification/epic.yaml
  next_skill: develop-tdd

Strategic compaction

Workflow

1. Initialize (Session Start)

If specs/state.yaml does not exist, or if starting a new major phase:

• Read specs/release-plan.yaml and specs/product/SCOPE_LATEST.yaml.
• Get git metadata: git branch --show-current and git rev-parse --short HEAD.
• Create specs/state.yaml with active flow, git, handoff, and epic cycle if in build.

2. Load (Context Refresh)

When starting a new session or after a significant context flush:

• Read specs/state.yaml to understand where the previous agent left off.
• Read specs/execution-status.yaml for story progress (do not infer from release-plan).
• Verify git matches state.yaml git.branch / git.hash.

3. Update (Decision Point/Milestone)

Whenever a significant decision is made or a milestone is reached:

• Patch via bash scripts/bp-yaml-set.sh specs/state.yaml git.hash <hash> (or edit directly).
• Patch handoff and learned_preferences / workspace_facts in CLAUDE.md fenced block when durable user preferences or repo facts crystallize (e45s23).
• Update handoff.open_decisions with rationale.
• Update epic_cycle when advancing ship-epic steps.
• Record open questions under handoff.open_decisions or an ADR.

→ verify: bash scripts/validate-specs-yaml.sh

Universal checkpoint pattern

Every multi-step flow (>3 steps) in bigpowers uses a cycle counter in state.yaml:

Checkpoint: After each step/phase completes, increment the counter in state.yaml and update handoff.next_skill.

Resume: On session start, read the current step/phase from the cycle key — continue from there, not from step 1.

Completed steps: Track completed steps in completed_steps (comma-separated string) for audit trail.

Strategic compaction

Print the current session state: cat specs/state.yaml, then display active_flow and handoff.next_skill for quick reference.

reset-state (absorbed)

Clear ephemeral session state. Set active_epic_id, active_story_id, and epic_cycle.current_step to null in specs/state.yaml. Use when ending a phase or starting a new project context.

compact-state (absorbed)

Archive verbose decisions before a context transition. Move all entries from handoff.open_decisions to their appropriate location:

• System-wide decisions → specs/adr/NNNN-slug.md (global Architectural Decision Records)
• Epic-scoped decisions → specs/epics/<active_epic_id>-<slug>/adr/NNNN-slug.md (epic-local ADRs, archived with epic)

After archiving, reset handoff.open_decisions to an empty list.

File Format: specs/state.yaml

active_flow: build_epic       # planning | build_epic | fix_bug
active_epic_id: e02
active_story_id: e02s01       # required when epic mode: folder
active_bug_id: null           # BUG-2026-06-01T143022 when fix_bug
release:
  target_version: null         # NOT tracked manually — semantic-release decides at merge
  last_tag: v2.28.0            # mirror of `gh release view`, reference only
  last_publish: null
epic_cycle:
  current_step: develop-tdd
  next_skill: develop-tdd
  completed_steps: [kickoff-branch]
bug_cycle:
  current_step: null
  completed_steps: []
git:
  branch: feat/e02-verify
  hash: abc1234
handoff:
  last_step_completed: null
  open_decisions: []
  next_skill: survey-context

Anti-Patterns

• Duplicate Plan: Don't copy release-plan.yaml or epic shards into state.yaml.
• Stale State: Forgetting to update state.yaml after a major refactor or decision.
• Status in release-plan: Story/epic status lives only in execution-status.yaml.