Implementation Plan: T5-P6-A6-WP1 Eliminate the batch_dispatch Phantom (#4126)

## Summary

Remove the unimplemented `batch_dispatch` ingredient from
`implementation.yaml`, delete the corresponding BATCH DISPATCH MODE
section from the fleet dispatcher prompt in `_prompts_kitchen.py`
(inserting a tombstone comment), clean up the now-dead
`max_issues_per_food_truck` parameter from the fleet prompt function,
delete 6 batch_dispatch-asserting contract tests, and regenerate derived
artifacts. The `implement-findings` recipe and campaign references are
preserved — only the phantom ingredient and its prompt section are
removed.

## Implementation Plan

Plan file:
`/home/talon/projects/autoskillit-runs/impl-20260627-053031-160994/.autoskillit/temp/make-plan/t5_p6_a6_wp1_batch_dispatch_phantom_plan_2026-06-27_054000.md`

Closes #4055

🤖 Generated with [Claude Code](https://claude.com/claude-code) via
AutoSkillit
<!-- autoskillit:pipeline-signature
steps=prepare_pr,run_arch_lenses,compose_pr,annotate_pr_diff,review_pr
-->

## Token Usage Summary

| Step | Model | count | uncached | output | cache_read | peak_ctx |
turns | cache_write | time |

|------|-------|-------|----------|--------|------------|----------|-------|-------------|------|
| plan* | opus[1m] | 1 | 57 | 16.9k | 1.4M | 90.3k | 52 | 75.3k | 13m
29s |
| verify* | sonnet | 1 | 1.2k | 8.9k | 383.7k | 54.2k | 26 | 35.7k | 5m
50s |
| implement* | MiniMax-M3 | 1 | 112.0k | 19.9k | 7.1M | 0 | 142 | 0 | 7m
57s |
| fix* | sonnet | 1 | 214 | 8.6k | 1.7M | 93.4k | 72 | 74.9k | 5m 18s |
| audit_impl* | sonnet | 1 | 44 | 12.2k | 163.7k | 42.5k | 15 | 37.5k |
6m 24s |
| prepare_pr* | MiniMax-M3 | 1 | 41.2k | 1.5k | 150.2k | 0 | 12 | 0 |
35s |
| compose_pr* | MiniMax-M3 | 1 | 36.4k | 1.5k | 140.5k | 0 | 13 | 0 |
24s |
| **Total** | | | 191.1k | 69.4k | 11.0M | 93.4k | | 223.4k | 40m 0s |

\* *Step used a non-Anthropic provider; caching behavior may differ.*

## Token Efficiency

| Step | LoC Changed | cache_read/LoC | cache_write/LoC | output/LoC |
|------|-------------|----------------|-----------------|------------|
| plan | 0 | — | — | — |
| verify | 0 | — | — | — |
| implement | 114 | 62466.2 | 0.0 | 174.7 |
| fix | 2 | 826046.0 | 37431.5 | 4281.5 |
| audit_impl | 0 | — | — | — |
| prepare_pr | 0 | — | — | — |
| compose_pr | 0 | — | — | — |
| **Total** | **116** | 94906.2 | 1925.9 | 598.6 |

## Model Usage Breakdown

| Model | steps | uncached | output | cache_read | cache_write | time |
|-------|-------|----------|--------|------------|-------------|------|
| opus[1m] | 1 | 57 | 16.9k | 1.4M | 75.3k | 13m 29s |
| sonnet | 3 | 1.5k | 29.6k | 2.2M | 148.1k | 17m 34s |
| MiniMax-M3 | 3 | 189.6k | 22.9k | 7.4M | 0 | 8m 57s |

Author: Trecek

src/autoskillit/cli/_prompts_kitchen.py

@@ -95,7 +95,6 @@ def _build_open_kitchen_prompt(
 def _build_fleet_dispatch_prompt(
     mcp_prefix: str,
     recipe_table: str | None = None,
-    max_issues_per_food_truck: int = 3,
     max_total_issues: int = 12,
     max_concurrent_dispatches: int = 3,
     has_unguarded_filesystem_access: bool = False,
@@ -265,38 +264,6 @@ def _build_fleet_dispatch_prompt(
 
 BEM already caps parallel group sizes via max_parallel (default 6 issues per group).
 
-## BATCH DISPATCH MODE — OPTIONAL
-
-When dispatching the `implementation` recipe for multiple issues and the user has set the
-`batch_dispatch` ingredient to `"true"`, use batched dispatch instead of per-issue dispatch:
-
-1. After BEM produces the dispatch_plan, for each parallel group (parallel: true):
-   a. Chunk the group's issues into sub-groups of up to {max_issues_per_food_truck} issues.
-   b. Dispatch each chunk as a SINGLE `implement-findings` food truck:
-      {mcp_prefix}dispatch_food_truck(
-          recipe="implement-findings",
-          task="Implement issues #X, #Y, #Z — parallel-safe per BEM group {{N}}",
-          ingredients={{{{
-              "issue_urls": "<comma-separated issue URLs for this chunk>",
-              "execution_map": "<captured execution_map from bem-wrapper>",
-              "base_branch": "<target branch>",
-          }}}},
-          dispatch_name="implement-g{{N}}-{{letter}}",
-      )
-   c. Name chunks sequentially: `implement-g{{N}}-a`, `-b`, `-c` …
-   d. Issue ALL chunks for a parallel group in a single response (parallel tool calls).
-      The fleet semaphore gates actual concurrency — if FLEET_PARALLEL_REFUSED is returned,
-      wait for a running dispatch to complete and retry.
-
-2. Groups with only 1 issue or sequential groups (parallel: false): dispatch via the
-   `implementation` recipe as normal — one food truck per issue, not batched.
-
-3. When `batch_dispatch` is `"false"` (the default): use the standard per-issue dispatch
-   from Step 4 above — one `implementation` food truck per issue. Do NOT use implement-findings.
-
-4. The execution_map captured from bem-wrapper MUST be passed as an ingredient to each
-   implement-findings food truck so BEM is not re-run inside the food truck.
-
 ## DISPATCHER DISCIPLINE
 
 You are a fleet dispatcher — NOT an executor. ALL recipe execution must be delegated \

src/autoskillit/cli/fleet/_fleet_session.py

@@ -71,7 +71,6 @@ def _launch_fleet_session(
         prompt = _build_fleet_dispatch_prompt(
             mcp_prefix,
             recipe_table=recipe_table,
-            max_issues_per_food_truck=cfg.fleet.max_issues_per_food_truck,
             max_total_issues=cfg.fleet.max_total_issues,
             max_concurrent_dispatches=cfg.fleet.max_concurrent_dispatches,
             has_unguarded_filesystem_access=_backend_caps.has_unguarded_filesystem_access,

src/autoskillit/recipes/diagrams/implementation.md

@@ -1,4 +1,4 @@
-<!-- autoskillit-recipe-hash: sha256:e5972fabca3a0bb471f4f99688ceaa78127056b33100574f05f355712fe50ffb -->
+<!-- autoskillit-recipe-hash: sha256:d3afca55385bea3028a28ec4354299c0fa8c03318976b921db7354eff380be57 -->
 <!-- autoskillit-diagram-format: v7 -->
 # implementation
 

src/autoskillit/recipes/implementation.json

@@ -55,10 +55,6 @@
       "description": "Automatically merge the PR after required checks pass — via merge queue when available, direct merge otherwise",
       "default": "true"
     },
-    "batch_dispatch": {
-      "description": "Pack multiple parallel-safe issues per food truck. When \"true\", the fleet dispatcher batches parallel-safe issues (up to max_issues_per_food_truck) into implement-findings food trucks with comma-separated issue_urls.",
-      "default": "false"
-    },
     "review_max_retries": {
       "description": "Maximum number of review-resolve retry cycles before proceeding to CI",
       "default": "3"

src/autoskillit/recipes/implementation.yaml

@@ -46,11 +46,6 @@ ingredients:
     description: Automatically merge the PR after required checks pass — via merge
       queue when available, direct merge otherwise
     default: 'true'
-  batch_dispatch:
-    description: Pack multiple parallel-safe issues per food truck. When "true", the
-      fleet dispatcher batches parallel-safe issues (up to max_issues_per_food_truck)
-      into implement-findings food trucks with comma-separated issue_urls.
-    default: 'false'
   review_max_retries:
     description: Maximum number of review-resolve retry cycles before proceeding to
       CI

tests/cli/test_fleet_session.py

@@ -809,33 +809,7 @@ async def test_build_fleet_campaign_prompt_accepts_prior_dispatch_id_parameter(
 
 
 class TestLaunchFleetSessionMaxIssuesPerFoodTruck:
-    """Contract: _launch_fleet_session threads max_issues_per_food_truck to prompt builders."""
-
-    def test_adhoc_dispatch_forwards_max_issues_per_food_truck(
-        self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path
-    ) -> None:
-        """Ad-hoc threads cfg.fleet.max_issues_per_food_truck to _build_fleet_dispatch_prompt."""
-        captured: dict = {}
-
-        def _fake_build(*args: object, **kwargs: object) -> str:
-            captured.update(kwargs)
-            return "fake-prompt"
-
-        monkeypatch.setattr("autoskillit.cli._prompts._build_fleet_dispatch_prompt", _fake_build)
-        monkeypatch.setattr(
-            "autoskillit.cli.session._session_launch._run_interactive_session",
-            lambda *a, **kw: None,
-        )
-
-        config_dir = tmp_path / ".autoskillit"
-        config_dir.mkdir(exist_ok=True)
-        (config_dir / "config.yaml").write_text("fleet:\n  max_issues_per_food_truck: 7\n")
-        monkeypatch.chdir(tmp_path)
-
-        from autoskillit.cli.fleet._fleet_session import _launch_fleet_session
-
-        _launch_fleet_session(None, None, None, None, fleet_mode="dispatch")
-        assert captured.get("max_issues_per_food_truck") == 7
+    """Contract: max_issues_per_food_truck flows to campaign builder only, not dispatch builder."""
 
     def test_campaign_dispatch_forwards_max_issues_per_food_truck(
         self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path
@@ -879,3 +853,10 @@ def _fake_build(
             fleet_mode="campaign",
         )
         assert captured.get("max_issues_per_food_truck") == 7
+
+    def test_dispatch_prompt_does_not_accept_max_issues_per_food_truck(self) -> None:
+        """_build_fleet_dispatch_prompt must not expose max_issues_per_food_truck parameter."""
+        from autoskillit.cli._prompts_kitchen import _build_fleet_dispatch_prompt
+
+        sig = inspect.signature(_build_fleet_dispatch_prompt)
+        assert "max_issues_per_food_truck" not in sig.parameters

tests/contracts/test_fleet_dispatch_bem_gate.py

@@ -98,51 +98,6 @@ def test_fleet_prompt_bem_gate_has_never_block(fleet_prompt: str) -> None:
     )
 
 
-def test_fleet_prompt_contains_batch_dispatch_section(fleet_prompt: str) -> None:
-    """Fleet dispatcher prompt must contain batch dispatch mode section."""
-    assert "BATCH DISPATCH" in fleet_prompt
-
-
-def test_fleet_prompt_batch_section_references_implement_findings(fleet_prompt: str) -> None:
-    """Batch dispatch section must reference implement-findings recipe."""
-    batch_section = fleet_prompt.split("BATCH DISPATCH")[1].split("## DISPATCHER")[0]
-    assert "implement-findings" in batch_section
-
-
-def test_fleet_prompt_batch_section_references_execution_map(fleet_prompt: str) -> None:
-    """Batch dispatch section must instruct passing execution_map to implement-findings."""
-    batch_section = fleet_prompt.split("BATCH DISPATCH")[1].split("## DISPATCHER")[0]
-    assert "execution_map" in batch_section
-
-
-def test_fleet_prompt_batch_section_contains_max_issues_cap(fleet_prompt: str) -> None:
-    """Batch dispatch section must contain the max_issues_per_food_truck cap value."""
-    batch_section = fleet_prompt.split("BATCH DISPATCH")[1].split("## DISPATCHER")[0]
-    assert "3" in batch_section
-
-
-def test_fleet_prompt_batch_section_preserves_single_issue_fallback(fleet_prompt: str) -> None:
-    """Batch section must instruct fallback to implementation recipe for single-issue groups."""
-    batch_section = fleet_prompt.split("BATCH DISPATCH")[1].split("## DISPATCHER")[0]
-    lower = batch_section.lower()
-    assert "single" in lower or "1 issue" in lower or "only 1" in lower
-
-
-def test_implementation_recipe_has_batch_dispatch_ingredient() -> None:
-    """implementation.yaml must expose a visible batch_dispatch ingredient."""
-    from autoskillit.core.io import load_yaml
-    from autoskillit.core.paths import pkg_root
-
-    recipe_yaml = load_yaml(pkg_root() / "recipes" / "implementation.yaml")
-    ingredients = recipe_yaml["ingredients"]
-    assert "batch_dispatch" in ingredients, (
-        "implementation.yaml must have batch_dispatch ingredient"
-    )
-    bd = ingredients["batch_dispatch"]
-    assert bd.get("default") == "false", "batch_dispatch must default to 'false'"
-    assert bd.get("hidden") is not True, "batch_dispatch must be visible (not hidden)"
-
-
 def test_fleet_prompt_contains_gated_group_handling(fleet_prompt: str) -> None:
     assert "gated" in fleet_prompt.lower(), (
         "Fleet dispatcher prompt must instruct handling of gated groups "