diff --git a/.conductor/registry/workflows/actionable.yaml b/.conductor/registry/workflows/actionable.yaml
index 6b1720e..483dbf5 100644
--- a/.conductor/registry/workflows/actionable.yaml
+++ b/.conductor/registry/workflows/actionable.yaml
@@ -176,7 +176,7 @@ agents:
   # Reads `workflow.input.executor`, validates it is one of the allowed
   # values, and emits `{ executor, work_item_id }` so the routes can
   # branch. Unknown executor values surface as an `error` field that
-  # falls through to workflow_error_gate.
+  # falls through to abort_run.
   #
   # Invariants:
   #   Pre:  workflow.input.executor is one of {polyphony, human}.
@@ -199,9 +199,9 @@ agents:
       - to: human_satisfaction_gate
         when: "{{ executor_router.output.executor == 'human' }}"
       # Catch-all per M4: an unknown executor value (router emits
-      # `output.error`) routes to the workflow error gate so a human
-      # decides retry/abandon rather than `No matching route found`.
-      - to: workflow_error_gate
+      # `output.error`) aborts deterministically rather than raising
+      # `No matching route found`.
+      - to: abort_run
 
   # ── Evidence branch ensure (polyphony leg) ──────────────────────────────
   #
@@ -235,7 +235,7 @@ agents:
       - "--from-ref"
       - "{{ workflow.input.from_ref }}"
     routes:
-      - to: workflow_error_gate
+      - to: abort_run
         when: "{{ ensure_evidence_branch.output.action == 'error' or (ensure_evidence_branch.output.error is defined and ensure_evidence_branch.output.error != '') }}"
       - to: compose_addendum
 
@@ -260,7 +260,7 @@ agents:
   #   Post: output.facets / output.skills / output.mcps / output.guidance
   #         / output.guidance_present are populated. On failure
   #         output.error and output.error_code are populated and the
-  #         workflow routes to workflow_error_gate; the agent never sees
+  #         workflow routes to abort_run; the agent never sees
   #         a partial envelope.
   - name: compose_addendum
     type: script
@@ -271,7 +271,7 @@ agents:
       - "compose-addendum"
       - "{{ workflow.input.work_item_id }}"
     routes:
-      - to: workflow_error_gate
+      - to: abort_run
         when: "{{ compose_addendum.output.error is defined and compose_addendum.output.error != '' }}"
       - to: guidance_loader
 
@@ -491,7 +491,7 @@ agents:
       - "--repository"
       - "{{ workflow.input.repository }}"
     routes:
-      - to: workflow_error_gate
+      - to: abort_run
         when: "{{ open_evidence_pr.output.error is defined and open_evidence_pr.output.error != '' }}"
       - to: evidence_floor_check
 
@@ -509,14 +509,12 @@ agents:
   # province. Do not extend with content-quality checks here.
   #
   # Routing (per the verb's routing-style envelope contract):
-  #   - error_code populated (pr_not_found / gh_failed) → workflow_error_gate
+  #   - error_code populated (pr_not_found / gh_failed) → abort_run
   #   - passes_floor == false                          → floor_failed_gate
   #   - passes_floor == true                           → evidence_reviewer
   #
   # The error_code branch fires before the floor branch because a
-  # transport failure means the floor was not actually evaluated — the
-  # error gate's retry path lets the operator re-run after fixing the
-  # underlying gh / network issue.
+  # transport failure means the floor was not actually evaluated.
   #
   # Invariants:
   #   Pre:  open_evidence_pr.output.pr_number > 0.
@@ -539,7 +537,7 @@ agents:
       - "--repository-override"
       - "{{ workflow.input.repository }}"
     routes:
-      - to: workflow_error_gate
+      - to: abort_run
         when: "{{ evidence_floor_check.output.error_code is defined and evidence_floor_check.output.error_code != null }}"
       - to: floor_failed_gate
         when: "{{ evidence_floor_check.output.passes_floor == false }}"
@@ -714,12 +712,11 @@ agents:
         when: "{{ evidence_reviewer.output.decision == 'approve' }}"
       - to: revise_loop_gate
         when: "{{ evidence_reviewer.output.decision == 'request_changes' }}"
-      - to: workflow_error_gate
+      - to: workflow_abandoned
         when: "{{ evidence_reviewer.output.decision == 'block' }}"
-      # Catch-all per M4: unknown / missing decision routes to the
-      # error gate so the operator decides rather than raising
-      # `No matching route found`.
-      - to: workflow_error_gate
+      # Catch-all per M4: unknown / missing decision abandons the workflow
+      # rather than raising `No matching route found`.
+      - to: workflow_abandoned
 
   # ── Revise loop gate (polyphony leg) ────────────────────────────────────
   #
@@ -804,10 +801,10 @@ agents:
     routes:
       - to: workflow_completed
         when: "{{ merge_evidence_pr.output.merged == true }}"
-      - to: workflow_error_gate
+      - to: workflow_abandoned
         when: "{{ merge_evidence_pr.output.merged == false }}"
-      # Catch-all per M4: missing/malformed merged field -> error gate.
-      - to: workflow_error_gate
+      # Catch-all per M4: missing/malformed merged field -> abandoned.
+      - to: workflow_abandoned
 
   # ── Human satisfaction gate (human leg) ────────────────────────────────
   #
@@ -851,71 +848,26 @@ agents:
         value: abandoned
         route: workflow_abandoned
 
-  # ── Workflow error gate (shared) ───────────────────────────────────────
+  # ── Terminal abort (deterministic workflow error) ──────────────────────
   #
-  # Fires on any error path — verb error envelope, reviewer block, or
-  # merge failure. Per P7 the retry option has no automatic cap; the
-  # human decides when to abandon. Retry re-enters at the executor
-  # router so a flipped-mind operator can change the executor input
-  # mid-recovery.
-  #
-  # Per M3 (StrictUndefined), every reference to a verb's output is
-  # guarded with `is defined` because at most one of the upstream verbs
-  # has actually populated an error envelope when this gate fires.
-  #
-  # Invariants:
-  #   Pre:  At least one upstream step has signaled an error.
-  #   Post: Operator chose retry (re-enter executor_router) or
-  #         abandon (workflow_abandoned).
-  - name: workflow_error_gate
-    type: human_gate
-    description: An error occurred — operator decides retry or abandon
-    prompt: |
-      ## ❌ Actionable workflow error — item #{{ workflow.input.work_item_id }}
-
-      An upstream step signaled an error or unrecoverable state.
-
-      {% if executor_router is defined and executor_router.output.error is defined and executor_router.output.error != '' -%}
-      **Stage:** executor_router
-      **Detail:** {{ executor_router.output.error }}
-      {%- elif ensure_evidence_branch is defined and ensure_evidence_branch.output.error is defined and ensure_evidence_branch.output.error != '' -%}
-      **Stage:** ensure_evidence_branch
-      **Detail:** {{ ensure_evidence_branch.output.error }}
-      {%- elif compose_addendum is defined and compose_addendum.output.error is defined and compose_addendum.output.error != '' -%}
-      **Stage:** compose_addendum
-      **Detail:** {{ compose_addendum.output.error }}{% if compose_addendum.output.error_code is defined %} ({{ compose_addendum.output.error_code }}){% endif %}
-      {%- elif open_evidence_pr is defined and open_evidence_pr.output.error is defined and open_evidence_pr.output.error != '' -%}
-      **Stage:** open_evidence_pr
-      **Detail:** {{ open_evidence_pr.output.error }}
-      {%- elif evidence_floor_check is defined and evidence_floor_check.output.error_code is defined and evidence_floor_check.output.error_code != null -%}
-      **Stage:** evidence_floor_check
-      **Detail:** [{{ evidence_floor_check.output.error_code }}] {{ evidence_floor_check.output.error_message }}
-      {%- elif evidence_reviewer is defined and evidence_reviewer.output.decision == 'block' -%}
-      **Stage:** evidence_reviewer
-      **Detail:** {{ evidence_reviewer.output.comment }}
-      {%- elif merge_evidence_pr is defined -%}
-      **Stage:** merge_evidence_pr
-      **Detail:** {% if merge_evidence_pr.output.error is defined %}{{ merge_evidence_pr.output.error }}{% else %}polyphony pr merge-evidence-pr reported merged=false (no error message){% endif %}
-      {%- else -%}
-      **Stage:** unknown
-      **Detail:** Routed to error gate without an explicit error envelope.
-      {%- endif %}
-
-      Choose an action:
-
-      - **Retry** — re-enter at the executor router. Both
-        `branch ensure-evidence-branch` and `pr open-evidence-pr` are
-        idempotent (existing branch / PR is reused). Safe regardless
-        of which stage failed.
-      - **Abandon** — terminate the workflow without satisfying the
-        item.
-    options:
-      - label: "🔄 Retry"
-        value: retry
-        route: executor_router
-      - label: "🛑 Abandon"
-        value: abandon
-        route: workflow_abandoned
+  # Invokes abort-run.ps1, which POSTs to conductor's /api/stop endpoint.
+  # Used for infrastructure errors that previously paused for human retry.
+  - name: abort_run
+    type: script
+    description: Deterministic actionable workflow abort — POSTs /api/stop to halt the run cleanly
+    command: pwsh
+    args:
+      - "-NoProfile"
+      - "-File"
+      - "{{ workflow.dir }}/../scripts/abort-run.ps1"
+      - "-Reason"
+      - "workflow-error"
+      - "-WorkItemId"
+      - "{{ workflow.input.work_item_id }}"
+      - "-Stage"
+      - "actionable"
+    routes:
+      - to: $end
 
   # ── Terminal: workflow completed ───────────────────────────────────────
   #
diff --git a/.conductor/registry/workflows/ado-pr.yaml b/.conductor/registry/workflows/ado-pr.yaml
index 4ed1968..bf15dd3 100644
--- a/.conductor/registry/workflows/ado-pr.yaml
+++ b/.conductor/registry/workflows/ado-pr.yaml
@@ -484,7 +484,8 @@ agents:
       - "--pr-number"
       - "{{ workflow.input.pr_number }}"
     routes:
-      - to: poll_error_gate
+      # on_error: auto-abort (AB#3257 — trivial gate removed; retry via conductor on_error: when Phase 1 ships)
+      - to: abort_run
         when: "{{ poll_status.output.error is defined and poll_status.output.error }}"
       - to: closed_unmerged_emitter
         when: "{{ poll_status.output.route == 'abort_unmerged' }}"
@@ -502,34 +503,6 @@ agents:
       # Catch-all per M4 — defensive deferral to analyzer.
       - to: pr_feedback_analyzer
 
-  # ── Poll error gate ───────────────────────────────────────────────────
-  - name: poll_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ PR Poll Failed — ADO PR #{{ workflow.input.pr_number }}
-
-      Could not read the PR review state for ADO PR
-      **#{{ workflow.input.pr_number }}**.
-
-      **State:** `{{ poll_status.output.state if poll_status.output.state is defined else "unknown" }}`
-      **Error:** {{ poll_status.output.error if poll_status.output.error is defined else "Unexpected state — check polyphony pr poll-status-ado output schema" }}
-
-      Common causes: missing/invalid PAT, ADO timeout, transient API
-      failure. Retry is safe (single read).
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-poll the PR
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔄 Retry"
-        value: retry
-        route: poll_status
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Already-merged emitter ────────────────────────────────────────────
   #
   # Operator completed the PR through the ADO UI (or it was completed via
diff --git a/.conductor/registry/workflows/github-pr.yaml b/.conductor/registry/workflows/github-pr.yaml
index e35b0bf..f720628 100644
--- a/.conductor/registry/workflows/github-pr.yaml
+++ b/.conductor/registry/workflows/github-pr.yaml
@@ -385,7 +385,8 @@ agents:
         }
         $json.Trim()
     routes:
-      - to: poll_error_gate
+      # on_error: auto-abort (AB#3257 — trivial gate removed; retry via conductor on_error: when Phase 1 ships)
+      - to: abort_run
         when: "{{ poll_status.output.error is defined and poll_status.output.error }}"
       - to: closed_unmerged_emitter
         when: "{{ poll_status.output.route == 'abort_unmerged' }}"
@@ -403,31 +404,6 @@ agents:
       # Catch-all per M4 — defensive deferral to analyzer.
       - to: pr_feedback_analyzer
 
-  # ── Poll error gate ───────────────────────────────────────────────────
-  - name: poll_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ PR Poll Failed — PR #{{ workflow.input.pr_number }}
-
-      Could not read the PR review state for PR
-      **#{{ workflow.input.pr_number }}**.
-
-      **State:** `{{ poll_status.output.state if poll_status.output.state is defined else "unknown" }}`
-      **Error:** {{ poll_status.output.error if poll_status.output.error is defined else "Unexpected state — check polyphony pr poll-status output schema" }}
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-poll the PR
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔄 Retry"
-        value: retry
-        route: poll_status
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Already-merged emitter ────────────────────────────────────────────
   #
   # Operator-merged the PR through the GitHub UI. Emit the canonical
diff --git a/.conductor/registry/workflows/implement-merge-group.yaml b/.conductor/registry/workflows/implement-merge-group.yaml
index 4e71f18..77b95b7 100644
--- a/.conductor/registry/workflows/implement-merge-group.yaml
+++ b/.conductor/registry/workflows/implement-merge-group.yaml
@@ -244,7 +244,8 @@ agents:
       # twig sync). Without this route the catch-all below silently
       # treats errors as "done with tasks" and proceeds toward MG
       # closure — masking real failures and leaving items unstarted.
-      - to: root_router_error_gate
+      # on_error: auto-abort (AB#3257 — trivial gate removed)
+      - to: abort_run
         when: "{{ root_router.output.action == 'error' or (root_router.output.error is defined and root_router.output.error != '') }}"
       # Catch-all per M4: unknown action from next-impl should fail
       # safely to dependency_check (the natural "we're done with tasks"
@@ -925,7 +926,7 @@ agents:
   #                  commit list to an operator via
   #                  squash_coverage_mismatch_gate.
   #   - 'error'    → verb itself failed (git invocation, ref resolution);
-  #                  surface to squash_coverage_error_gate for retry/abort.
+  #                  auto-abort via abort_run (AB#3257).
   #
   # Invariants:
   #   Pre:  Squash committed to `origin/mg/{root}_{path}`; local ref
@@ -958,7 +959,8 @@ agents:
         to: delete_impl_branch
       - when: "{{ assert_impl_pr_coverage.output.action == 'mismatch' }}"
         to: squash_coverage_mismatch_gate
-      - to: squash_coverage_error_gate
+      # on_error: auto-abort (AB#3257 — trivial gate removed)
+      - to: abort_run
 
   # ── Coverage mismatch gate (AB#3211) ──────────────────────────────────
   #
@@ -1023,46 +1025,6 @@ agents:
         value: force_accept
         route: delete_impl_branch
 
-  # ── Coverage assertion error gate (AB#3211) ───────────────────────────
-  #
-  # Fires when `assert-impl-pr-coverage` itself returns action='error'
-  # (typically a git invocation failure: missing ref, transient network).
-  # Distinct from the mismatch gate — this is a tool failure, not a
-  # data-loss incident.
-  - name: squash_coverage_error_gate
-    type: human_gate
-    description: assert-impl-pr-coverage tool error — operator decides retry or abort
-    prompt: |
-      ## ⚠️ Coverage assertion failed to run — task `{{ root_router.output.root_id }}`
-
-      `polyphony pr assert-impl-pr-coverage` returned an error envelope
-      (the verb itself could not complete; this is a tool failure, not
-      a coverage mismatch).
-
-      **Detail:** {{ assert_impl_pr_coverage.output.error | default('(no error message)') }}
-
-      | Field | Value |
-      |---|---|
-      | Impl ref | `{{ assert_impl_pr_coverage.output.impl_ref | default('(unresolved)') }}` |
-      | MG ref | `{{ assert_impl_pr_coverage.output.mg_ref | default('(unresolved)') }}` |
-
-      Common causes: stale local refs (re-fetch may help), missing
-      `origin/impl/{root}-{item}` (impl branch deleted prematurely),
-      transient git failure.
-
-      Choose an action:
-
-      - **Retry** — re-run the fetch + assertion. Use after manual
-        recovery (e.g. `git fetch origin`).
-      - **Abort** — END this workflow without deleting the impl branch.
-    options:
-      - label: "🔄 Retry (re-fetch + re-assert)"
-        value: retry
-        route: fetch_for_coverage_assertion
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Delete impl branch (deferred from impl_pr_merge per AB#3211) ──────
   #
   # Performs the branch deletion that `merge-impl-pr` would normally do
@@ -1222,60 +1184,6 @@ agents:
     routes:
       - to: root_router
 
-  # ── Primary router error gate ─────────────────────────────────────────
-  #
-  # Fires when `branch next-impl` (root_router) emits action='error' or
-  # a non-empty `error` field. Without an explicit route, the catch-all
-  # below would silently treat the error as "all items done" and proceed
-  # toward MG closure — masking the failure and skipping every remaining
-  # task.
-  #
-  # AB#3126 root cause coupling: next-impl now flushes its
-  # begin_implementation transition via a post-state `twig sync` before
-  # returning. Network/auth blips during that sync surface here as
-  # action='error'.
-  #
-  # Operator options:
-  #   - Retry: re-enter root_router. `next-impl` is idempotent —
-  #     transitions a Doing item to Doing is a no-op for the validator
-  #     (begin_implementation accepts both Proposed and InProgress), and
-  #     the second `twig sync` will retry the push.
-  #   - Abort: $end. The MG remains in its current state; no items are
-  #     advanced to Done. Re-running the workflow later resumes from the
-  #     same point.
-  #
-  # Invariants:
-  #   Pre:  root_router emitted action='error' or a populated `error`.
-  #   Post: Operator has retried (route to root_router) or aborted ($end).
-  - name: root_router_error_gate
-    type: human_gate
-    description: next-impl signaled error — operator decides retry or abort
-    prompt: |
-      ## ❌ next-impl error — MG `mg/{{ workflow.input.root_id }}_{{ workflow.input.mg_path }}`
-
-      `polyphony branch next-impl` returned an error envelope. The most
-      common cause is a transient ADO failure during the post-state
-      `twig sync` that flushes the `begin_implementation` transition
-      (AB#3126).
-
-      **Detail:** {{ root_router.output.error | default('(no error message)') }}
-
-      Choose an action:
-
-      - **Retry** — re-enter `root_router`. `next-impl` is idempotent
-        (selecting the same task again, validating `begin_implementation`
-        on a Doing item, and re-flushing all are no-ops or safe retries).
-      - **Abort** — exit without advancing any further items. The MG
-        remains in its current state; a later workflow re-entry resumes
-        from the same point.
-    options:
-      - label: "🔄 Retry (re-run next-impl)"
-        value: retry
-        route: root_router
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Dependency check ──────────────────────────────────────────────────
   #
   # Checks ADO predecessor links to determine if the MG is blocked by
diff --git a/.conductor/registry/workflows/plan-level.yaml b/.conductor/registry/workflows/plan-level.yaml
index 910caf0..29c6c7c 100644
--- a/.conductor/registry/workflows/plan-level.yaml
+++ b/.conductor/registry/workflows/plan-level.yaml
@@ -315,7 +315,7 @@ agents:
     routes:
       - to: root_fallback_gate
         when: "{{ root_resolver.output.fallback_required == true }}"
-      - to: root_resolver_error_gate
+      - to: abort_run
         when: "{{ root_resolver.output.error is defined and root_resolver.output.error }}"
       - to: type_loader
 
@@ -343,26 +343,6 @@ agents:
         value: abort
         route: abort_run
 
-  # ── Root resolver error gate ──────────────────────────────────────────
-  - name: root_resolver_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Root Resolution Failed
-
-      Could not resolve the run root for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Error:** {{ root_resolver.output.error if root_resolver.output.error is defined else "Unknown error — check that the work item exists in ADO." }}
-
-      ---
-
-      Choose an action:
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Type loader ──────────────────────────────────────────────────────────
   #
   # Loads type-specific context from .polyphony-config/work-item-types/. Outputs
@@ -379,27 +359,7 @@ agents:
     routes:
       - to: ancestor_chain
         when: "{{ type_loader.output.type is defined and type_loader.output.type != '' }}"
-      - to: type_loader_error_gate
-
-  # ── Type loader error gate ───────────────────────────────────────────────
-  - name: type_loader_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Type Context Load Failed
-
-      Planning for work item **{{ workflow.input.work_item_id }}** cannot continue
-      because the type context could not be loaded.
-
-      **Error:** {{ type_loader.output.error if type_loader.output.error is defined else "Unknown error — check that .polyphony-config/work-item-types/ is configured and the work item exists in ADO." }}
-
-      ---
-
-      Choose an action:
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
+      - to: abort_run
 
   # ── Ancestor chain derivation ─────────────────────────────────────────
   #
@@ -421,34 +381,10 @@ agents:
       - "--item-id"
       - "{{ workflow.input.work_item_id }}"
     routes:
-      - to: ancestor_chain_error_gate
+      - to: abort_run
         when: "{{ ancestor_chain.output.error is defined and ancestor_chain.output.error }}"
       - to: state_detector
 
-  # ── Ancestor chain error gate ─────────────────────────────────────────
-  - name: ancestor_chain_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Ancestor Chain Derivation Failed
-
-      Could not derive the plan-tree ancestor chain for work item
-      **{{ workflow.input.work_item_id }}** under root
-      **{{ root_resolver.output.resolved_root_id }}**.
-
-      **Error:** {{ ancestor_chain.output.error if ancestor_chain.output.error is defined else "Unknown error" }}
-
-      Common causes: work item is not actually a descendant of the root,
-      the parent chain is broken, or a cycle was detected.
-
-      ---
-
-      Choose an action:
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── State detector ────────────────────────────────────────────────────
   #
   # The single oracle for "where is this plan tree branch right now?"
@@ -492,7 +428,7 @@ agents:
       - "--repository-override"
       - "{{ workflow.input.repository }}"
     routes:
-      - to: state_detector_error_gate
+      - to: abort_run
         when: "{{ state_detector.output.state == 'error' }}"
       - to: child_router
         when: "{{ state_detector.output.state == 'complete' }}"
@@ -511,31 +447,8 @@ agents:
         when: "{{ state_detector.output.state == 'stale_generation' }}"
       - to: architect
         when: "{{ state_detector.output.state == 'not_started' }}"
-      # Catch-all per M4: unexpected state value should surface as a gate,
-      # not raise mid-run "no matching route".
-      - to: state_detector_error_gate
-
-  # ── State detector error gate ─────────────────────────────────────────
-  - name: state_detector_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Plan State Detection Failed
-
-      Could not detect plan-tree state for work item
-      **{{ workflow.input.work_item_id }}** under root
-      **{{ root_resolver.output.resolved_root_id }}**.
-
-      **State:** `{{ state_detector.output.state if state_detector.output.state is defined else "unknown" }}`
-      **Error:** {{ state_detector.output.error if state_detector.output.error is defined else "Unexpected state value — check polyphony plan detect-state output schema" }}
-
-      ---
-
-      Choose an action:
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
+      # Catch-all per M4: unexpected state value; abort deterministically (AB#3257).
+      - to: abort_run
 
   # ── Closed-unmerged gate ───────────────────────────────────────────────
   #
@@ -1036,34 +949,10 @@ agents:
       - "--children-json"
       - "{{ architect.output.children | tojson }}"
     routes:
-      - to: write_plan_error_gate
+      - to: abort_run
         when: "{{ write_plan.output.error is defined and write_plan.output.error }}"
       - to: commit_and_push
 
-  # ── Write plan error gate ──────────────────────────────────────────────
-  - name: write_plan_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Plan Write Failed
-
-      Could not write the plan for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Error:** {{ write_plan.output.error if write_plan.output.error is defined else "Unknown error" }}
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-run `polyphony plan write-plan` (idempotent)
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔁 Retry"
-        value: retry
-        route: write_plan
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Ensure plan branch ────────────────────────────────────────────────
   #
   # Idempotently creates (or fast-forwards to) the plan branch and checks
@@ -1090,35 +979,10 @@ agents:
       - "--parent-item-id"
       - "{{ ancestor_chain.output.parent_item_id | default(0) }}"
     routes:
-      - to: ensure_plan_branch_error_gate
+      - to: abort_run
         when: "{{ ensure_plan_branch.output.error is defined and ensure_plan_branch.output.error }}"
       - to: write_plan
 
-  # ── Ensure plan branch error gate ─────────────────────────────────────
-  - name: ensure_plan_branch_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Plan Branch Setup Failed
-
-      Could not create or check out the plan branch for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Error:** {{ ensure_plan_branch.output.error if ensure_plan_branch.output.error is defined else "Unknown error" }}
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-run `polyphony branch ensure-plan` (idempotent;
-        recovers from transient git-network failures)
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔁 Retry"
-        value: retry
-        route: ensure_plan_branch
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Commit and push ────────────────────────────────────────────────────
   #
   # Stages plans/plan-{item_id}.md, commits with a deterministic message,
@@ -1148,7 +1012,7 @@ agents:
       - "--paths"
       - "plans/plan-{{ workflow.input.work_item_id }}.md,plans/plan-{{ workflow.input.work_item_id }}.children.json"
     routes:
-      - to: commit_and_push_error_gate
+      - to: abort_run
         when: "{{ commit_and_push.output.error is defined and commit_and_push.output.error }}"
       # v2.1: route through pr_open_platform_router so the same
       # commit-and-push leg can feed either open_plan_pr (github) or
@@ -1156,33 +1020,6 @@ agents:
       # no-op fall-through.
       - to: pr_open_platform_router
 
-  # ── Commit and push error gate ────────────────────────────────────────
-  - name: commit_and_push_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Plan Commit/Push Failed
-
-      Could not commit and push the plan for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Branch:** `{{ ensure_plan_branch.output.branch }}`
-      **Error:** {{ commit_and_push.output.error if commit_and_push.output.error is defined else "Unknown error" }}
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-run `polyphony plan commit-and-push` (idempotent;
-        emits no_changes when nothing is staged, recovers from transient
-        push-network failures)
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔁 Retry"
-        value: retry
-        route: commit_and_push
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Open plan PR ───────────────────────────────────────────────────────
   #
   # Opens the plan PR (or returns the existing one) and embeds the
@@ -1212,41 +1049,10 @@ agents:
       - "--ancestor-ids"
       - "{{ ancestor_chain.output.ancestor_ids }}"
     routes:
-      - to: open_plan_pr_error_gate
+      - to: abort_run
         when: "{{ open_plan_pr.output.error is defined and open_plan_pr.output.error }}"
       - to: plan_reviewer
 
-  # ── Open plan PR error gate ────────────────────────────────────────────
-  - name: open_plan_pr_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Plan PR Open Failed
-
-      Could not open the plan PR for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Branch:** `{{ ensure_plan_branch.output.branch }}`
-      **Error:** {{ open_plan_pr.output.error if open_plan_pr.output.error is defined else "Unknown error" }}
-
-      Common causes: stale ancestor snapshot on an existing PR (operator
-      must close/recreate); gh authentication missing; network timeout
-      (gh rate-limit, GitHub API hiccup, DNS); transient gh process hang.
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-run `polyphony pr open-plan-pr` (idempotent — reuses
-        an existing PR with a matching ancestor snapshot; safe for
-        transient gh/network failures)
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔁 Retry"
-        value: retry
-        route: open_plan_pr
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Plan reviewer (LLM advisory — sentiment-driven model) ─────────────
   #
   # Single LLM reviewer per design doc Q2. Produces a critique using a
@@ -1509,7 +1315,7 @@ agents:
       - "{{ open_plan_pr.output.pr_url if (open_plan_pr is defined and open_plan_pr.output.pr_url is defined) else state_detector.output.pr_url }}"
       - "--include-metadata"
     routes:
-      - to: poll_error_gate
+      - to: abort_run
         when: "{{ poll_status.output.error is defined and poll_status.output.error }}"
       # Terminal: operator merged through the platform UI.
       - to: seeder
@@ -1531,31 +1337,6 @@ agents:
       # Catch-all per M4 — defensive; treat unknown as deferral to analyzer.
       - to: pr_feedback_analyzer
 
-  # ── Poll error gate ───────────────────────────────────────────────────
-  - name: poll_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Plan PR Poll Failed
-
-      Could not read the plan PR review state for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **State:** `{{ poll_status_ado.output.state if (poll_status_ado is defined and poll_status_ado.output.state is defined) else (poll_status.output.state if (poll_status is defined and poll_status.output.state is defined) else "unknown") }}`
-      **Error:** {{ poll_status_ado.output.error if (poll_status_ado is defined and poll_status_ado.output.error is defined) else (poll_status.output.error if (poll_status is defined and poll_status.output.error is defined) else "Unexpected state — check polyphony pr poll-status / poll-status-ado output schema") }}
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-poll the PR
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔄 Retry"
-        value: retry
-        route: pr_poll_platform_router
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Extract parent patch (P8d wiring) ──────────────────────────────────
   #
   # Reached when either (a) state_detector returns parent_change_pending —
@@ -2346,7 +2127,8 @@ agents:
     routes:
       - to: stale_generation_gate
         when: "{{ merge_plan_pr.output.error_code is defined and merge_plan_pr.output.error_code == 'stale_generation' }}"
-      - to: merge_error_gate
+      # on_error: auto-abort (AB#3257 — trivial gate removed; cause info in run event log)
+      - to: abort_run
         when: "{{ merge_plan_pr.output.error_code is defined and merge_plan_pr.output.error_code != '' and merge_plan_pr.output.error_code != 'stale_generation' }}"
       - to: extract_renegotiation_flag
 
@@ -2473,99 +2255,6 @@ agents:
     routes:
       - to: merge_plan_pr
 
-  # ── Merge error gate ──────────────────────────────────────────────────
-  #
-  # Cause-aware: surfaces the verb's full diagnostic message (which is
-  # already specific — e.g. worktree_dirty includes the porcelain entry
-  # count and remediation hint) and then a per-error-code "Next step"
-  # block tailored to what the operator actually needs to do before
-  # retrying. Falls back to a generic message for codes not yet enumerated
-  # so a new error_code never silently regresses to "no guidance shown".
-  - name: merge_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Plan PR Merge Failed
-
-      Could not merge the plan PR for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Error code:** `{{ merge_plan_pr.output.error_code }}`
-
-      {% if merge_plan_pr.output.error is defined and merge_plan_pr.output.error %}
-      **Details:** {{ merge_plan_pr.output.error }}
-      {% endif %}
-
-      ---
-
-      **Next step:**
-      {% if merge_plan_pr.output.error_code == 'worktree_dirty' %}
-      The worktree has uncommitted changes. From the run's worktree
-      directory, run `git status` to see what's there, then commit,
-      stash, or discard the changes before retrying. Common culprit:
-      stray scratch files left behind by an agent tool call (look for
-      orphan `.txt` / `.json` files at the repo root).
-      {% elif merge_plan_pr.output.error_code == 'lock_held' %}
-      Another polyphony run holds the same-root run lock. Check for an
-      in-flight workflow on the same root; wait for it to finish, or
-      use `polyphony lock force-release` if it's a stale lock.
-      {% elif merge_plan_pr.output.error_code == 'lock_stale' %}
-      The run lock is older than the staleness threshold. Run
-      `polyphony lock force-release --root-id <id>` to clear it, then
-      retry.
-      {% elif merge_plan_pr.output.error_code == 'manifest_push_rejected' %}
-      A concurrent run pushed to the manifest branch first. Retry —
-      the verb will refetch and re-attempt; usually succeeds on the
-      next try.
-      {% elif merge_plan_pr.output.error_code in ['repo_not_resolved', 'config_error'] %}
-      Configuration / environment issue. Check that gh is authenticated
-      to the right user (`gh auth status`), the repo slug resolves, and
-      the run's `.conductor` config is valid. Retry once fixed.
-      {% elif merge_plan_pr.output.error_code == 'pr_not_found' %}
-      The PR number on record no longer exists on the platform.
-      Someone may have closed or deleted it manually. Aborting and
-      restarting plan-level for this work item is usually safer than
-      retrying.
-      {% elif merge_plan_pr.output.error_code in ['head_ref_mismatch', 'base_ref_mismatch'] %}
-      The PR's head or base branch doesn't match what the manifest
-      expects. Inspect the PR on the platform — it may have been
-      retargeted manually. Aborting and re-opening the PR via
-      plan-level is safer than retrying.
-      {% elif merge_plan_pr.output.error_code == 'pr_state_unmergeable' %}
-      The platform reports the PR is not in a mergeable state
-      (conflicts, failing required checks, blocked by branch protection).
-      Resolve the underlying block on the PR page, then retry.
-      {% elif merge_plan_pr.output.error_code == 'merge_failed' %}
-      The platform's merge call returned an error. Check the PR page
-      for the platform-specific reason, address it, then retry.
-      {% elif merge_plan_pr.output.error_code in ['missing_merge_commit', 'ledger_conflict'] %}
-      Post-merge bookkeeping failed. Manifest may be partially
-      updated. Inspect the manifest branch before retrying.
-      {% elif merge_plan_pr.output.error_code == 'validation_blocked' %}
-      A pre-merge validation check rejected the merge. See **Details**
-      above for the specific rule that blocked it; remediate, then
-      retry.
-      {% elif merge_plan_pr.output.error_code == 'internal_error' %}
-      Unexpected verb-internal failure. Capture the run's event log
-      and file a polyphony issue. Retry is safe but may reproduce.
-      {% else %}
-      No targeted guidance for this error code. See **Details** above
-      and inspect the run's event log for context. Retry is safe but
-      may reproduce.
-      {% endif %}
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-attempt the merge
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔄 Retry"
-        value: retry
-        route: merge_plan_pr
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Seeder ─────────────────────────────────────────────────────────────
   #
   # Idempotent seeder. Consumes architect.output.children and reconciles
@@ -2625,66 +2314,10 @@ agents:
       - "--children-from-ref"
       - "origin/main"
     routes:
-      - to: seeder_error_gate
+      - to: child_router
         when: "{{ seeder.output.error_count is defined and seeder.output.error_count > 0 }}"
       - to: child_router
 
-  # ── Seeder error gate (AB#3067) ─────────────────────────────────────────
-  #
-  # `polyphony plan seed-children` always exits 0 and carries per-child
-  # failures in `errors[]`. This gate fires when `error_count > 0` so the
-  # operator sees the failure rather than continuing into child_router with
-  # a half-seeded tree (which silently terminates the root blocked).
-  #
-  # Retry routes back to `seeder` because the verb is idempotent — it
-  # reconciles against existing children via marker-aware matching, so
-  # re-running after fixing the upstream cause (e.g. resolving a duplicate
-  # title) is safe.
-  - name: seeder_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Seeder Reported Errors
-
-      `polyphony plan seed-children` for work item
-      **{{ workflow.input.work_item_id }}** returned
-      `error_count = {{ seeder.output.error_count if seeder.output.error_count is defined else 'unknown' }}`.
-
-      The seeder is idempotent — it reconciles architect-emitted
-      children against existing children of the parent work item.
-      Common causes:
-      - Duplicate child title under the parent (twig dedup conflict).
-      - Invalid or inaccessible parent ID at the platform layer.
-      - Twig workspace misconfiguration.
-
-      **Errors (truncated to a first line per item):**
-      {%- if seeder.output.errors is defined %}
-      {%- for e in seeder.output.errors %}
-      - `{{ e.child_id if e.child_id is defined and e.child_id else (e.title if e.title is defined and e.title else '(unknown)') }}` — {{ e.error if e.error is defined else '(no detail)' }}
-      {%- endfor %}
-      {%- else %}
-      _(no per-child error envelopes — see verb stderr in run logs)_
-      {%- endif %}
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-run the seeder (idempotent; safe after fixing the
-        upstream cause, e.g. resolving a duplicate title)
-      - **Continue** — proceed to `child_router` anyway (a partial seed is
-        usually still useful; the next driver iteration will revisit any
-        children that did get created)
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔁 Retry"
-        value: retry
-        route: seeder
-      - label: "▶️  Continue"
-        value: continue
-        route: child_router
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Child router ─────────────────────────────────────────────────────────
   #
   # Discovers plannable children of the current work item. Filters by
@@ -2829,41 +2462,10 @@ agents:
       - "--ancestor-ids"
       - "{{ ancestor_chain.output.ancestor_ids }}"
     routes:
-      - to: open_plan_pr_ado_error_gate
+      - to: abort_run
         when: "{{ open_plan_pr_ado.output.error is defined and open_plan_pr_ado.output.error }}"
       - to: plan_reviewer
 
-  # ── Open plan PR (ADO) error gate ─────────────────────────────────────
-  - name: open_plan_pr_ado_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ ADO Plan PR Open Failed
-
-      Could not open (or reuse) the plan PR on Azure DevOps for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Branch:** `{{ ensure_plan_branch.output.branch }}`
-      **Error:** {{ open_plan_pr_ado.output.error if open_plan_pr_ado.output.error is defined else "Unknown error" }}
-
-      Common causes: stale ancestor snapshot on an existing PR (operator
-      must abandon/recreate); ADO PAT missing or insufficient scope;
-      network timeout; repository identifier mismatch.
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-run `polyphony pr open-plan-pr-ado` (idempotent —
-        reuses an existing PR with a matching ancestor snapshot; safe for
-        transient ADO API / network failures)
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔁 Retry"
-        value: retry
-        route: open_plan_pr_ado
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Plan reviewer poster (ADO) ────────────────────────────────────────
   #
   # Posts the comment body produced by plan_reviewer to the ADO PR via
@@ -2939,7 +2541,7 @@ agents:
       - "--include-metadata"
       - "--allow-any-approval-vote"
     routes:
-      - to: poll_error_gate
+      - to: abort_run
         when: "{{ poll_status_ado.output.error is defined and poll_status_ado.output.error }}"
       - to: seeder
         when: "{{ poll_status_ado.output.route == 'already_merged' }}"
@@ -2988,7 +2590,7 @@ agents:
       # use a dedicated gate.
       - to: merge_plan_pr_ado_stale_gate
         when: "{{ merge_plan_pr_ado.output.error_code is defined and merge_plan_pr_ado.output.error_code == 'stale_generation' }}"
-      - to: merge_plan_pr_ado_error_gate
+      - to: abort_run
         when: "{{ merge_plan_pr_ado.output.error_code is defined and merge_plan_pr_ado.output.error_code != '' and merge_plan_pr_ado.output.error_code != 'stale_generation' }}"
       - to: restack_remedy
 
@@ -3033,34 +2635,6 @@ agents:
     routes:
       - to: merge_plan_pr_ado
 
-  # ── Merge plan PR (ADO) error gate ────────────────────────────────────
-  - name: merge_plan_pr_ado_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ ADO Plan PR Merge Failed
-
-      Could not merge the plan PR for work item
-      **{{ workflow.input.work_item_id }}**.
-
-      **Error code:** `{{ merge_plan_pr_ado.output.error_code }}`
-
-      Common causes: lock acquisition failed (another run holds the
-      same-root lock); push conflict on manifest branch; ADO PAT auth;
-      stale head SHA; reviewer requirements not met.
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-attempt the merge
-      - **Abort** — halt the entire run (terminates the conductor process)
-    options:
-      - label: "🔄 Retry"
-        value: retry
-        route: merge_plan_pr_ado
-      - label: "🛑 Abort"
-        value: abort
-        route: abort_run
-
   # ── Plan children summary gate ───────────────────────────────────────────
   #
   # Fires only when one or more child planning sub-workflows failed.
diff --git a/.conductor/registry/workflows/restack-remedy.yaml b/.conductor/registry/workflows/restack-remedy.yaml
index da54c0b..ead9f99 100644
--- a/.conductor/registry/workflows/restack-remedy.yaml
+++ b/.conductor/registry/workflows/restack-remedy.yaml
@@ -99,9 +99,9 @@ agents:
       - "--repository-override"
       - "{{ workflow.input.repository }}"
     routes:
-      # Verb-level error (manifest read/parse, repo slug, etc.) — surface
-      # to the restack-error gate so the operator can decide.
-      - to: classify_error_gate
+      # Verb-level error (manifest read/parse, repo slug, etc.) — auto-skip.
+      # on_error: auto-skip (AB#3257 — trivial gate removed; routes to $end on classify error)
+      - to: $end
         when: "{{ classify.output.error_code is defined and classify.output.error_code != null and classify.output.error_code != '' }}"
       # Nothing stale — done.
       - to: $end
@@ -109,35 +109,6 @@ agents:
       # At least one stale entry — fan out remedies.
       - to: remedy_group
 
-  # ── Classify error gate ───────────────────────────────────────────────
-  - name: classify_error_gate
-    type: human_gate
-    prompt: |
-      ## ⚠️ Restack Classify Failed
-
-      `polyphony plan classify-stale-descendants` could not enumerate
-      stale descendants for root **{{ workflow.input.root_id }}**.
-
-      - **Error code:** `{{ classify.output.error_code }}`
-      - **Error:** {{ classify.output.error | default('(none)') }}
-
-      Common causes: manifest missing or malformed in the per-root state
-      directory (`<git-common-dir>/polyphony/{{ workflow.input.root_id }}/run.yaml`),
-      repo slug not resolvable from `origin`, twig cache stale.
-
-      ---
-
-      Choose an action:
-      - **Retry** — re-run the classifier (after fixing the cause).
-      - **Skip restack** — exit without remediating descendant PRs.
-    options:
-      - label: "🔄 Retry classify"
-        value: retry
-        route: classify
-      - label: "⏭️ Skip restack"
-        value: skip
-        route: $end
-
   # ── Restack summary gate ──────────────────────────────────────────────
   #
   # Fires only when remedy_group.errors is non-empty (i.e. at least one
diff --git a/docs/projects/on-error-migration-inventory.md b/docs/projects/on-error-migration-inventory.md
index 7ee9156..0f2b35f 100644
--- a/docs/projects/on-error-migration-inventory.md
+++ b/docs/projects/on-error-migration-inventory.md
@@ -1,6 +1,6 @@
 # on_error Migration Inventory
 
-**Status:** Read-only inventory; informs AB#3257 sequencing
+**Status:** Migration complete as of #528; conductor on_error: retry support pending AB#3257 Phase 1
 **Owner:** polyphony-internal architecture
 **Work item:** AB#3257 — Failure-mode gate elimination
 **Companion:** [conductor on_error brief](https://github.com/PolyphonyRequiem/conductor/blob/02eace858dbaf2d1d22598a6e7debdf2d4c8a439/docs/projects/error-routing/on-error-routing.brainstorm.md)