diff --git a/codev-skeleton/protocols/aspir/builder-prompt.md b/codev-skeleton/protocols/aspir/builder-prompt.md
index 48ec8a425..266fd7b96 100644
--- a/codev-skeleton/protocols/aspir/builder-prompt.md
+++ b/codev-skeleton/protocols/aspir/builder-prompt.md
@@ -53,13 +53,23 @@ Follow the implementation plan at: `{{plan.path}}`
 {{task_text}}
 {{/if}}
 
-## Multi-PR Workflow
+## PR Strategy
 
-Your worktree is persistent — it survives across PR merges. You can produce multiple PRs sequentially:
+**Do not autonomously open a PR per implementation phase.** Plan phases ship as git commits within a single PR, not as separate PRs. The plan's instruction that "each phase commits independently" refers to git commits, not PRs.
+
+By default, the PR is opened during/after the final implement phase, with all phase-commits already on the branch.
+
+### Architect-requested PRs
+
+The architect MAY request a PR at any point — for spec review, mid-implementation feedback, slicing a large spec into shippable PRs, etc. When the architect explicitly asks for a PR earlier (or for additional PRs), follow that direction. The prohibition is specifically on the *builder* autonomously deciding to open per-phase PRs without architect request.
+
+### Multi-PR Mechanics (when the architect requests sequential PRs)
+
+Your worktree is persistent — it survives across PR merges. When the architect asks for sequential PRs (e.g., to slice a large spec into shippable pieces), use this loop:
 
 1. Cut a branch, open a PR, wait for merge
 2. After merge: `git fetch origin main && git checkout -b <next-branch> origin/main`
-3. Continue to the next phase, open another PR
+3. Continue to the next slice, open another PR
 
 **Important**: Do NOT run `git checkout main` — git worktrees cannot check out a branch that's checked out elsewhere. Always branch off `origin/main` via fetch.
 
diff --git a/codev-skeleton/protocols/spir/builder-prompt.md b/codev-skeleton/protocols/spir/builder-prompt.md
index 1abf4b289..4e4e81d8f 100644
--- a/codev-skeleton/protocols/spir/builder-prompt.md
+++ b/codev-skeleton/protocols/spir/builder-prompt.md
@@ -53,13 +53,23 @@ Follow the implementation plan at: `{{plan.path}}`
 {{task_text}}
 {{/if}}
 
-## Multi-PR Workflow
+## PR Strategy
 
-Your worktree is persistent — it survives across PR merges. You can produce multiple PRs sequentially:
+**Do not autonomously open a PR per implementation phase.** Plan phases ship as git commits within a single PR, not as separate PRs. The plan's instruction that "each phase commits independently" refers to git commits, not PRs.
+
+By default, the PR is opened during/after the final implement phase, with all phase-commits already on the branch.
+
+### Architect-requested PRs
+
+The architect MAY request a PR at any point — for spec review, mid-implementation feedback, slicing a large spec into shippable PRs, etc. When the architect explicitly asks for a PR earlier (or for additional PRs), follow that direction. The prohibition is specifically on the *builder* autonomously deciding to open per-phase PRs without architect request.
+
+### Multi-PR Mechanics (when the architect requests sequential PRs)
+
+Your worktree is persistent — it survives across PR merges. When the architect asks for sequential PRs (e.g., to slice a large spec into shippable pieces), use this loop:
 
 1. Cut a branch, open a PR, wait for merge
 2. After merge: `git fetch origin main && git checkout -b <next-branch> origin/main`
-3. Continue to the next phase, open another PR
+3. Continue to the next slice, open another PR
 4. Repeat
 
 **Important**: Do NOT run `git checkout main` — git worktrees cannot check out a branch that's checked out elsewhere. Always branch off `origin/main` via fetch.
diff --git a/codev/projects/bugfix-744-spir-builder-prompt-ambiguous-/status.yaml b/codev/projects/bugfix-744-spir-builder-prompt-ambiguous-/status.yaml
new file mode 100644
index 000000000..654c26321
--- /dev/null
+++ b/codev/projects/bugfix-744-spir-builder-prompt-ambiguous-/status.yaml
@@ -0,0 +1,12 @@
+id: bugfix-744
+title: spir-builder-prompt-ambiguous-
+protocol: bugfix
+phase: verified
+plan_phases: []
+current_plan_phase: null
+gates: {}
+iteration: 1
+build_complete: false
+history: []
+started_at: '2026-05-14T20:58:56.293Z'
+updated_at: '2026-05-14T21:12:13.608Z'
diff --git a/codev/protocols/aspir/builder-prompt.md b/codev/protocols/aspir/builder-prompt.md
index 2715ed877..3ea4c9fac 100644
--- a/codev/protocols/aspir/builder-prompt.md
+++ b/codev/protocols/aspir/builder-prompt.md
@@ -53,6 +53,16 @@ Follow the implementation plan at: `{{plan.path}}`
 {{task_text}}
 {{/if}}
 
+## PR Strategy
+
+**Do not autonomously open a PR per implementation phase.** Plan phases ship as git commits within a single PR, not as separate PRs. The plan's instruction that "each phase commits independently" refers to git commits, not PRs.
+
+By default, the PR is opened during/after the final implement phase, with all phase-commits already on the branch.
+
+### Architect-requested PRs
+
+The architect MAY request a PR at any point — for spec review, mid-implementation feedback, slicing a large spec into shippable PRs, etc. When the architect explicitly asks for a PR earlier (or for additional PRs), follow that direction. The prohibition is specifically on the *builder* autonomously deciding to open per-phase PRs without architect request.
+
 ## Notifications
 Always use `afx send architect "..."` to notify the architect at key moments:
 - **Gate reached**: `afx send architect "Project {{project_id}}: <gate-name> ready for approval"`
diff --git a/codev/protocols/spir/builder-prompt.md b/codev/protocols/spir/builder-prompt.md
index c905b4696..e3afa0e79 100644
--- a/codev/protocols/spir/builder-prompt.md
+++ b/codev/protocols/spir/builder-prompt.md
@@ -53,6 +53,16 @@ Follow the implementation plan at: `{{plan.path}}`
 {{task_text}}
 {{/if}}
 
+## PR Strategy
+
+**Do not autonomously open a PR per implementation phase.** Plan phases ship as git commits within a single PR, not as separate PRs. The plan's instruction that "each phase commits independently" refers to git commits, not PRs.
+
+By default, the PR is opened during/after the final implement phase, with all phase-commits already on the branch.
+
+### Architect-requested PRs
+
+The architect MAY request a PR at any point — for spec review, mid-implementation feedback, slicing a large spec into shippable PRs, etc. When the architect explicitly asks for a PR earlier (or for additional PRs), follow that direction. The prohibition is specifically on the *builder* autonomously deciding to open per-phase PRs without architect request.
+
 ## Notifications
 Always use `afx send architect "..."` to notify the architect at key moments:
 - **Gate reached**: `afx send architect "Project {{project_id}}: <gate-name> ready for approval"`
diff --git a/packages/codev/src/__tests__/bugfix-744-spir-pr-strategy.test.ts b/packages/codev/src/__tests__/bugfix-744-spir-pr-strategy.test.ts
new file mode 100644
index 000000000..4a4d2aa7e
--- /dev/null
+++ b/packages/codev/src/__tests__/bugfix-744-spir-pr-strategy.test.ts
@@ -0,0 +1,60 @@
+/**
+ * Regression test for GitHub Issue #744
+ *
+ * The SPIR/ASPIR builder-prompt templates did not state the PR-strategy
+ * convention explicitly. Builders interpreted "each phase commits
+ * independently" as "each phase gets its own PR" and shipped per-phase
+ * PRs that the architect then had to close.
+ *
+ * This test verifies that all four SPIR/ASPIR builder-prompt files contain:
+ *   1. An explicit prohibition on the builder autonomously opening a PR
+ *      per implementation phase.
+ *   2. The clarification that "each phase commits independently" refers
+ *      to git commits, not PRs.
+ *   3. The architect-override carve-out — the architect may still request
+ *      a PR at any point (spec review, mid-impl feedback, slicing, etc.).
+ */
+
+import { describe, it, expect } from 'vitest';
+import * as fs from 'node:fs';
+import * as path from 'node:path';
+
+const repoRoot = path.resolve(__dirname, '..', '..', '..', '..');
+
+const PROMPT_FILES = [
+  'codev/protocols/spir/builder-prompt.md',
+  'codev-skeleton/protocols/spir/builder-prompt.md',
+  'codev/protocols/aspir/builder-prompt.md',
+  'codev-skeleton/protocols/aspir/builder-prompt.md',
+];
+
+describe('bugfix-744: SPIR/ASPIR builder-prompt PR strategy', () => {
+  for (const relPath of PROMPT_FILES) {
+    const fullPath = path.join(repoRoot, relPath);
+
+    it(`${relPath} — prohibits builder from autonomously opening per-phase PRs`, () => {
+      const content = fs.readFileSync(fullPath, 'utf-8');
+      expect(content).toMatch(/Do not autonomously open a PR per implementation phase/);
+    });
+
+    it(`${relPath} — clarifies phase-commits are git commits, not PRs`, () => {
+      const content = fs.readFileSync(fullPath, 'utf-8');
+      expect(content).toMatch(/refers to git commits, not PRs/);
+    });
+
+    it(`${relPath} — preserves architect-override carve-out`, () => {
+      const content = fs.readFileSync(fullPath, 'utf-8');
+      // The architect must be explicitly allowed to request a PR at any point —
+      // the prohibition is on autonomous builder action, not on PRs themselves.
+      expect(content).toMatch(/architect MAY request a PR/i);
+    });
+
+    it(`${relPath} — states the default PR-timing (during/after final implement phase)`, () => {
+      const content = fs.readFileSync(fullPath, 'utf-8');
+      // The new default replaces the old rigid "ONE PR per spec, opened at the end of
+      // the implement phase" wording. Builders need to know *when* the default PR opens
+      // so they don't fall back to per-phase PRs in the absence of architect direction.
+      expect(content).toMatch(/By default, the PR is opened during\/after the final implement phase/);
+    });
+  }
+});