diff --git a/openspec/changes/manifest-version-bump/design.md b/openspec/changes/manifest-version-bump/design.md
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+# Design: Manifest version bump
+
+## Status
+proposed
+
+## Spec kind & sizing (ADR-032)
+
+- `kind: config` — touches only `src/manifest.json`. Zero `lib/`,
+  zero `src/components/`, zero `src/views/`, zero `tests/` edits.
+- Smallest possible diff: 1 character changed (`3` → `4` in version string).
+- Scope: 1 file, 1 task, ~2 builder turns expected.
+
+## Declarative-vs-imperative decision (ADR-031)
+
+Not applicable to this change — manifest versioning is pure declarative
+content (no behaviour change, no service-vs-schema choice).
+
+## Impact on existing code
+
+- `src/manifest.json`: `"version": "0.3.0"` → `"version": "0.4.0"`.
+- **Nothing else.** Frontend bundle still rebuilds the same manifest;
+  `useAppManifest()` reads the same shape; `CnAppRoot` renders identically.
+- No backend impact (the manifest is frontend-only).
+- No test impact (manifest validation runs via `npm run check:manifest`,
+  which validates schema-shape, not version semantics).
+
+## Reuse Analysis (ADR-001)
+
+Not applicable — no new behaviour, no abstraction reuse to evaluate.
+
+## Deduplication Check (ADR-001)
+
+Not applicable — this is a single-field metadata bump, no duplication
+risk.
+
+## Risks
+
+1. **Caching**: a bumped manifest version invalidates any client-side
+   manifest cache. Acceptable — Tier 4 already loads the bundled manifest
+   on every page load.
+2. **Reviewer false-positive on "no functional change"**: the reviewer
+   might flag this as low-value and request more context. The proposal
+   explicitly names the test-of-pipeline rationale.
+
+## Out of scope
+
+- Any other manifest field change.
+- Any non-manifest file edit.
+- Documentation updates beyond this spec set.
diff --git a/openspec/changes/manifest-version-bump/proposal.md b/openspec/changes/manifest-version-bump/proposal.md
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+---
+kind: config
+depends_on: []
+---
+
+# Manifest version bump (0.3.0 → 0.4.0)
+
+## Problem
+
+Decidesk's `src/manifest.json` is at `version: "0.3.0"`. Per ADR-024 §7,
+`manifest.version` tracks semver of content; an app bumps the minor while
+iterating. The manifest has accumulated meaningful content evolution since
+0.3.0 landed (full Tier 4 adoption, declarative business-logic specs in
+flight, ADR-032 chain pattern adopted). A minor-version bump records that
+maturation as a content-versioning waypoint.
+
+This change is also the **smallest possible Hydra config-only spec** —
+deliberately scoped to validate the Stage A pipeline end-to-end (build →
+quality → review → security → applier) on a one-line diff with zero
+semantic risk. If this fails, the pipeline has bugs unrelated to spec
+content; if it passes, the bigger ADR-031 chain specs can run with
+confidence.
+
+## Proposed Solution
+
+Edit `src/manifest.json`: change `"version": "0.3.0"` → `"version": "0.4.0"`.
+
+That is the entire change. No code, no schemas, no tests, no documentation
+updates beyond this proposal/design/tasks set.
+
+## Capabilities
+
+### Modified Capabilities
+
+- `app-manifest` — manifest.version increments per ADR-024 §7.
+
+### New Capabilities
+
+(none)
+
+## Stakeholders
+
+- **Decidesk maintainers** — own the bump.
+- **Hydra reviewers** — validates the config-only flow end-to-end on the
+  smallest possible diff.
+
+## References
+
+- ADR-024 (hydra) — App Manifest, §7 versioning rules
+- ADR-032 (hydra) — Spec sizing taxonomy; this spec is the canonical
+  `kind: config` minimal example
+- `decidesk/src/manifest.json` — target file
diff --git a/openspec/changes/manifest-version-bump/tasks.md b/openspec/changes/manifest-version-bump/tasks.md
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+# Tasks: Manifest version bump
+
+> **`kind: config`** — single 1-character edit in `src/manifest.json`.
+> No PHP, no Vue, no tests added. The smallest possible Hydra spec.
+
+## 1. Bump manifest version
+
+- [ ] Edit `src/manifest.json`: change `"version": "0.3.0"` to
+      `"version": "0.4.0"`.
+- [ ] Verify the diff is exactly one line, exactly one character.
+
+## 2. Verification (mechanical)
+
+- [ ] `jq '.version' src/manifest.json` returns `"0.4.0"`.
+- [ ] `npm run check:manifest` exits 0 (schema validates).
+- [ ] `git diff --stat origin/development...HEAD` shows
+      `src/manifest.json | 2 +-` (one line removed, one line added —
+      jq doesn't preserve formatting around the bump, but the net
+      change is one field).
+
+## 3. Commit + PR
+
+The Hydra builder commits and the wrapper auto-creates the draft PR.
+No additional manual action expected from the implementer.
+
+## Deduplication Check
+
+- [ ] Confirmed: no duplication. This is a single-field metadata bump,
+      no abstractions involved.
+
+---
+
+## Notes for the implementer
+
+This spec is the canonical `kind: config` minimal example, drafted
+2026-05-08 to validate the Hydra config-only flow end-to-end on the
+smallest possible diff. Expected wall time: 15-25 minutes for the full
+pipeline (build → quality → reviewer → security → applier).
+
+If you find yourself touching anything other than `src/manifest.json`,
+**stop** — that's out of scope for this spec.