diff --git a/.github/workflows/pr-risk.yml b/.github/workflows/pr-risk.yml
index 53c07c4..308ccf4 100644
--- a/.github/workflows/pr-risk.yml
+++ b/.github/workflows/pr-risk.yml
@@ -3,9 +3,10 @@ name: PR Risk Grade (reusable)
 # Reusable ADVISORY PR risk grader — the shadow-check rung of the PR risk-grading ladder.
 # Grades every PR event into a tier R0 (safest) .. R3 (riskiest) and syncs ONE label
 # (`risk:R0` .. `risk:R3`, or `risk:ungraded` when an input was unreadable). That label is
-# the entire product: nothing is gated, nothing is blocked, nothing merges, no comment is
-# posted. Humans look at the label and agree or disagree; disagreement is recorded by adding
-# the `risk-dispute` label (which this workflow never touches) plus a comment saying why.
+# the entire product: nothing is gated, nothing is blocked and nothing merges. Humans record a
+# different assessment with `risk-dispute:R0` .. `risk-dispute:R3`, either as a label or with
+# `/risk-dispute R2 [optional reason]`. The legacy `risk-dispute` label and `/risk-dispute
+# [optional reason]` remain tier-unspecified disputes. Neither changes the computed `risk:R*`.
 #
 # grade = worst(path_floor, provenance, reversibility) — three deterministic axes; the worst
 # tier wins, so no axis can move a PR into a safer lane than another axis put it. No LLM, no
@@ -63,8 +64,8 @@ name: PR Risk Grade (reusable)
 #
 # ON-DEMAND GRADING (`pr_number` / `pr_numbers`): supply a PR number and that PR is graded with
 # no `pull_request` event involved — which is how a repo enrolling mid-stream grades the open
-# queue it already has, and how a PR is re-graded after a `.github/risk.json` change or a
-# `risk-dispute`. Absent, the workflow reads the event exactly as before. Three things differ on
+# queue it already has, and how a PR is re-graded after a `.github/risk.json` change. Absent, the
+# workflow reads the event exactly as before. Three things differ on
 # the by-number path, all of them deliberate:
 #   * BOT-AUTHORED PRs ARE GRADED. The `github.actor != 'dependabot[bot]'` clause callers put in
 #     their `if:` is a TOKEN guard, not a policy one: a bot-triggered `pull_request` run gets a
@@ -106,7 +107,7 @@ name: PR Risk Grade (reusable)
 # labels on a PR under one `label_map`; remapping `label_map` orphans the old names, which is a
 # one-time repo-side cleanup. What the shape does cost is a narrower residual: the PUT is built from
 # a snapshot read, so a NON-owned label added by someone else in the read→PUT window is dropped
-# (`risk-dispute` included) and one removed in it is resurrected. That window opens only on a run
+# (`risk-dispute` forms included) and one removed in it is resurrected. That window opens only on a run
 # that actually changes the grade and is roughly one API round-trip — about three on the first
 # grade in a repo, where the label pre-create sits inside it. The drop is recorded on the PR
 # timeline as an `unlabeled` event, so re-add a dispute that happens to land in that instant.
@@ -116,8 +117,8 @@ name: PR Risk Grade (reusable)
 # quiet.
 #
 # SECRETS: none. This workflow declares no `secrets:` inputs and callers pass none — the only
-# credential in the job is the automatic `GITHUB_TOKEN` (`github.token`), used for the PR read
-# and the one label write. There is no `secrets: inherit` to add and nothing to rotate.
+# credential in the job is the automatic `GITHUB_TOKEN` (`github.token`), used for PR reads,
+# labels and dispute audit comments. There is no `secrets: inherit` to add and nothing to rotate.
 #
 # The label is applied with the plain GITHUB_TOKEN on purpose: GITHUB_TOKEN-applied labels
 # cannot fire `labeled` triggers, so the shadow check is structurally unable to start a
@@ -136,7 +137,9 @@ name: PR Risk Grade (reusable)
 #   name: CI - PR Risk Grade
 #   on:
 #     pull_request:
-#       types: [opened, synchronize, reopened, ready_for_review]
+#       types: [opened, synchronize, reopened, ready_for_review, labeled, unlabeled]
+#     issue_comment:
+#       types: [created]
 #     workflow_dispatch:
 #       inputs:
 #         pr_number:
@@ -154,7 +157,7 @@ name: PR Risk Grade (reusable)
 #     # A `pr_numbers` LIST keys its own group, which serializes identical batches but cannot
 #     # serialize a batch against a `pull_request` run for one of its members — see "A BATCH
 #     # CANNOT SERIALIZE PER-PR" above for what that costs and how to avoid it.
-#     group: ${{ github.workflow }}-${{ inputs.pr_numbers || inputs.pr_number || github.event.pull_request.number }}
+#     group: ${{ github.workflow }}-${{ inputs.pr_numbers || inputs.pr_number || github.event.pull_request.number || github.event.issue.number }}
 #     cancel-in-progress: true
 #   permissions:
 #     contents: read
@@ -171,8 +174,12 @@ name: PR Risk Grade (reusable)
 #       # on a dispatch the token is writable and the actor is a human, so there is nothing left
 #       # for either clause to protect.
 #       if: >-
-#         github.event_name != 'pull_request' ||
-#         (github.actor != 'dependabot[bot]' &&
+#         github.event_name != 'issue_comment' &&
+#         (github.event_name != 'pull_request' ||
+#          ((github.event.action != 'labeled' && github.event.action != 'unlabeled') ||
+#           github.event.label.name == 'risk-dispute' ||
+#           startsWith(github.event.label.name, 'risk-dispute:')) &&
+#          github.actor != 'dependabot[bot]' &&
 #          github.event.pull_request.head.repo.full_name == github.repository)
 #       permissions:
 #         contents: read
@@ -211,6 +218,24 @@ name: PR Risk Grade (reusable)
 #         # For a backfill, dispatch with this lowered — see ON-DEMAND GRADING above for why a
 #         # low wait is sound on the by-number path and why `0` still is not the right value.
 #         # wait_for_checks_minutes: 1
+#     risk-dispute-comment:
+#       if: >-
+#         github.event.issue.pull_request &&
+#         (github.event.comment.body == '/risk-dispute' ||
+#          startsWith(github.event.comment.body, '/risk-dispute '))
+#       permissions:
+#         contents: read
+#         issues: write
+#         pull-requests: write
+#         checks: write
+#         actions: read
+#         statuses: read
+#       uses: Comfy-Org/github-workflows/.github/workflows/pr-risk.yml@<sha>  # v1
+#       with:
+#         workflows_ref: <same sha>
+#         enabled: true
+#         pr_number: ${{ github.event.issue.number }}
+#         wait_for_checks_minutes: 1
 #
 # A SKIPPED CALLER JOB IS INVISIBLE FROM HERE. This workflow cannot detect, warn about or recover
 # from a caller whose `if:` excluded it — no run is created, so nothing of ours executes. The
@@ -244,8 +269,8 @@ on:
           `pull_request` run: with no number supplied the target, the base ref and every emitted
           label are exactly what they were before this input existed. Supplying it is what makes
           grading possible without a `pull_request` event — the enrollment backfill of an
-          already-open queue, and the manual re-grade after a risk-map change or a
-          `risk-dispute`. Bot-authored and fork PRs ARE graded on this path (see the header).
+          already-open queue, and the manual re-grade after a risk-map change.
+          Bot-authored and fork PRs ARE graded on this path (see the header).
           Typed `string` rather than `number` because `workflow_dispatch` inputs arrive as
           strings, and because an empty string is what lets the fall-through to the event's own
           number stay a single expression.
@@ -294,6 +319,14 @@ on:
         type: string
         required: false
         default: ''
+      allowed_dispute_associations:
+        description: >-
+          Comma-separated author associations allowed to use `/risk-dispute`.
+          Label-based disputes already require label permission; this gate applies
+          to the comment command. Use commas with no spaces.
+        type: string
+        required: false
+        default: 'OWNER,MEMBER,COLLABORATOR'
       wait_for_checks_minutes:
         description: >-
           How long to wait, PER TARGET, for the REST of the check rollup to settle before
@@ -338,10 +371,9 @@ on:
 
           Ticking the checkbox applies `risk-grade-disputed` on the next grade, and a re-grade
           preserves the tick rather than resetting it. That label is DISTINCT from the
-          human-owned `risk-dispute` convention, which the grader still never touches: one is a
-          machine-maintained mirror of a checkbox, rewritten on every grade; the other is a
-          human's own label. Needs no permission beyond the `pull-requests: write` the grade job
-          already holds for the label.
+          human-owned `risk-dispute` and `risk-dispute:R*` labels: one mirrors a checkbox, while
+          the others record a disagreement with an optional human tier. Needs no permission beyond
+          the `pull-requests: write` the grade job already holds for the label.
         type: boolean
         required: false
         default: false
@@ -728,8 +760,14 @@ jobs:
     # lockout. If a repo ever needs the harder guarantee, remove the caller — nothing here can
     # bind a maintainer who can edit the workflow file anyway.
     if: >-
-      needs.gate.outputs.enabled == 'true' ||
-      github.event_name == 'workflow_dispatch'
+      (needs.gate.outputs.enabled == 'true' ||
+       github.event_name == 'workflow_dispatch') &&
+      (github.event_name != 'issue_comment' ||
+       (github.event.issue.pull_request &&
+        (github.event.comment.body == '/risk-dispute' ||
+         startsWith(github.event.comment.body, '/risk-dispute ')) &&
+        contains(format(',{0},', inputs.allowed_dispute_associations),
+                 format(',{0},', github.event.comment.author_association))))
     name: Grade PR risk
     runs-on: ubuntu-latest
     timeout-minutes: 30
@@ -958,6 +996,34 @@ jobs:
           set -uo pipefail
           bash _pr_risk_tool/scripts/pr-risk/grade-targets.sh
 
+      - name: Record risk dispute
+        if: >-
+          always() && !cancelled() &&
+          (github.event_name == 'issue_comment' ||
+           (github.event_name == 'pull_request' &&
+            (github.event.action == 'opened' ||
+             github.event.action == 'reopened' ||
+             github.event.action == 'ready_for_review' ||
+             github.event.action == 'labeled' ||
+             github.event.action == 'unlabeled' ||
+             github.event.action == 'synchronize')))
+        env:
+          REPO: ${{ github.repository }}
+          PR_NUMBER: ${{ inputs.pr_number || github.event.pull_request.number || github.event.issue.number }}
+          RECORD: record-${{ inputs.pr_number || github.event.pull_request.number || github.event.issue.number }}.json
+          EVENT_NAME: ${{ github.event_name }}
+          EVENT_ACTION: ${{ github.event.action }}
+          EVENT_LABEL: ${{ github.event.label.name }}
+          COMMENT_BODY: ${{ github.event.comment.body }}
+          COMMENT_ID: ${{ github.event.comment.id }}
+          COMMENT_URL: ${{ github.event.comment.html_url }}
+          ACTOR: ${{ github.event.sender.login || github.actor }}
+          ACTOR_ASSOCIATION: ${{ github.event.comment.author_association }}
+          ALLOWED_ASSOCIATIONS: ${{ inputs.allowed_dispute_associations }}
+          RUN_ID: ${{ github.run_id }}
+          GH_TOKEN: ${{ github.token }}
+        run: bash _pr_risk_tool/scripts/pr-risk/handle-risk-dispute.sh
+
       - name: Step summary
         if: always()
         env:
@@ -1060,7 +1126,7 @@ jobs:
               jq -r '"| #\(.pr) | \(.tier // "—") | \(.label // "—") | `\(.base_ref // "—")` | \(.waited)s | \(.note // "") |"' "$RESULTS"
             fi
             echo
-            echo "This label routes nothing and gates nothing. Disagree with the grade? Add the \`risk-dispute\` label and say why in a comment — the grader never touches that label."
+            echo "This label routes nothing and gates nothing. Record a human assessment with \`risk-dispute:R0\`…\`R3\` or \`/risk-dispute R0\`…\`R3 [optional reason]\`. Legacy \`risk-dispute\` remains a tier-unspecified disagreement; neither form changes \`risk:R*\`."
           } >> "$GITHUB_STEP_SUMMARY"
 
   # THE ONE JOB THAT HOLDS `checks: write`, and it reads NOTHING from a pull request. Its whole
diff --git a/.github/workflows/test-pr-risk.yml b/.github/workflows/test-pr-risk.yml
index c70d045..cc8d7dd 100644
--- a/.github/workflows/test-pr-risk.yml
+++ b/.github/workflows/test-pr-risk.yml
@@ -48,7 +48,7 @@ jobs:
           persist-credentials: false
 
       - name: shellcheck
-        run: shellcheck -x grade-pr-risk.sh apply-risk-label.sh grade-targets.sh resolve-enabled.sh tests/test_grade_pr_risk.sh tests/test_apply_risk_label.sh tests/test_grade_targets.sh tests/test_resolve_enabled.sh tests/test_pin_contract.sh publish-risk-surfaces.sh tests/test_publish_risk_surfaces.sh
+        run: shellcheck -x grade-pr-risk.sh apply-risk-label.sh grade-targets.sh handle-risk-dispute.sh resolve-enabled.sh tests/test_grade_pr_risk.sh tests/test_apply_risk_label.sh tests/test_grade_targets.sh tests/test_handle_risk_dispute.sh tests/test_resolve_enabled.sh tests/test_pin_contract.sh publish-risk-surfaces.sh tests/test_publish_risk_surfaces.sh
 
       - name: default map + registry parse and validate
         # The shipped defaults must pass the grader's own structural validation:
@@ -69,6 +69,9 @@ jobs:
         # every call it receives is logged, so the suite asserts on which requests were made.
         run: bash tests/test_grade_targets.sh
 
+      - name: risk-dispute suite
+        run: bash tests/test_handle_risk_dispute.sh
+
       - name: pin-contract suite
         # The `workflows_ref` guard in pr-risk.yml itself — the trust boundary that decides which
         # revision of this repo's grader runs, and the one piece of logic that CANNOT live in a
diff --git a/docs/callers/pr-risk.md b/docs/callers/pr-risk.md
index bf95d1c..ee1d839 100644
--- a/docs/callers/pr-risk.md
+++ b/docs/callers/pr-risk.md
@@ -6,9 +6,10 @@ Read [the shared caller contract](README.md) first.
 
 Grades every PR into a tier `R0` (safest) .. `R3` (riskiest) and syncs **one**
 label (`risk:R0`..`risk:R3`, or `risk:ungraded` when an input was unreadable).
-The label is the entire product: nothing is gated, routed, commented, or
-merged — a human looks at the label and agrees or disagrees (recorded with a
-`risk-dispute` label this workflow never touches).
+Nothing is gated, routed, or merged. A human can record a different assessment
+beside the computed label with `risk-dispute:R0` through `risk-dispute:R3`.
+The legacy plain `risk-dispute` marker remains valid with no human tier; neither
+form changes the computed `risk:R*`.
 
 Deterministic, no LLM: `grade = worst(path_floor, provenance, reversibility)` —
 a path-glob map, what process produced the diff (registered runbooks, forks
@@ -37,10 +38,12 @@ on:
   # a fork run under plain `pull_request` cannot write the label. See the
   # fork gotcha below before you swap it.
   pull_request:
-    types: [opened, synchronize, reopened, ready_for_review]
+    types: [opened, synchronize, reopened, ready_for_review, labeled, unlabeled]
+  issue_comment:
+    types: [created]
 
 concurrency:
-  group: pr-risk-${{ github.event.pull_request.number }}
+  group: pr-risk-${{ github.event.pull_request.number || github.event.issue.number }}
   cancel-in-progress: true
 
 permissions:
@@ -48,6 +51,14 @@ permissions:
 
 jobs:
   pr-risk:
+    if: >-
+      github.event_name != 'issue_comment' &&
+      (github.event_name != 'pull_request' ||
+       (((github.event.action != 'labeled' && github.event.action != 'unlabeled') ||
+         github.event.label.name == 'risk-dispute' ||
+         startsWith(github.event.label.name, 'risk-dispute:')) &&
+        github.actor != 'dependabot[bot]' &&
+        github.event.pull_request.head.repo.full_name == github.repository))
     permissions:
       contents: read
       issues: write          # create the risk:* labels repo-side on first use
@@ -61,6 +72,26 @@ jobs:
     uses: Comfy-Org/github-workflows/.github/workflows/pr-risk.yml@<full-commit-sha>
     with:
       workflows_ref: <same-full-commit-sha>
+      enabled: true
+
+  risk-dispute-comment:
+    if: >-
+      github.event.issue.pull_request &&
+      (github.event.comment.body == '/risk-dispute' ||
+       startsWith(github.event.comment.body, '/risk-dispute '))
+    permissions:
+      contents: read
+      issues: write
+      pull-requests: write
+      checks: write
+      actions: read
+      statuses: read
+    uses: Comfy-Org/github-workflows/.github/workflows/pr-risk.yml@<full-commit-sha>
+    with:
+      workflows_ref: <same-full-commit-sha>
+      enabled: true
+      pr_number: ${{ github.event.issue.number }}
+      wait_for_checks_minutes: 1
 ```
 
 Enrolling is **two steps** — merging the caller above is only the first. Ask a
@@ -118,10 +149,39 @@ fail the caller's next run at startup.
 | `fleet_logins` | `mattmillerai` | Logins whose PRs grade provenance `agent-supervised` alongside `agent-coded`. Both are read for **human** authors only: an author GitHub types as a `Bot` is a runbook candidate regardless, so listing a bot here (or labelling its PR) buys it nothing — only a registry entry that asserts can promote it. |
 | `bot_logins` | `github-actions,dependabot,renovate,coderabbitai,cursor,comfy-pr-bot,web-flow` | Extra logins treated as bots. Needed only for **machine USER accounts** — a real GitHub App is recognized from GitHub's own actor type, no list entry required. A bot with no runbook entry still grades as human — identity alone buys no trust. **This list is load-bearing, not a hint:** a listed login skips the first-time-contributor test, so it moves a non-fork `NONE`/`FIRST_TIME_CONTRIBUTOR` PR from `external` (R3) to `human` (R1). Nothing validates that a listed login is really a machine account, so add one only for an account you control, and remove it when it is retired. |
 | `label_map` | `''` | Rename the five grader-owned labels as `tier=label` pairs. Tier keys are fixed; only the label text is yours. |
+| `allowed_dispute_associations` | `OWNER,MEMBER,COLLABORATOR` | Comment authors allowed to use `/risk-dispute`. Comma-separated with no spaces. Direct label changes already require repository label permission. |
 | `wait_for_checks_minutes` | `10` | How long to wait for the rest of the check rollup to settle before labeling (clamped to 25 — what a 30-minute job can spend waiting). `0` labels immediately, expect R2 floors from still-pending checks. |
 | `repo_map_path` | `.github/risk.json` | Consumer risk-map override, read from the PR **base ref**. |
 | `repo_runbooks_path` | `.github/risk-runbooks.json` | Consumer runbook-registry override, read from the PR **base ref**. |
 
+## Risk disputes
+
+A human assessment sits beside the computed grade; it never replaces it:
+
+```text
+risk:R1
+risk-dispute:R2
+```
+
+Apply `risk-dispute:R0` through `risk-dispute:R3` directly, or comment:
+
+```text
+/risk-dispute R2 Optional reason
+```
+
+The legacy forms remain supported as a disagreement with no human-assessed tier:
+
+```text
+risk-dispute
+/risk-dispute Optional reason
+```
+
+The reason may be empty or continue on later lines. A tiered dispute replaces
+the legacy label and any previous tier. `/risk-dispute clear` clears both forms;
+removing a label clears that form, and a new push expires both. Each change posts
+a bot-authored audit record with the computed tier, nullable human tier, head
+SHA, source, actor and optional reason.
+
 ## Gotchas
 
 **Fork PRs need `pull_request_target`, not `pull_request`.** A fork PR under a
diff --git a/scripts/pr-risk/README.md b/scripts/pr-risk/README.md
index 1b8a4a6..32f8e4d 100644
--- a/scripts/pr-risk/README.md
+++ b/scripts/pr-risk/README.md
@@ -11,10 +11,12 @@ event is graded into a tier and gets ONE label:
 | R3 | `risk:R3` | elevated — auth, billing, migrations, IaC, CI, deps, secrets | owner + e2e |
 | — | `risk:ungraded` | an input could not be read; deliberately NOT a tier | human review |
 
-**The label is the entire product.** Nothing is gated, blocked, routed, commented
-on, or merged. Humans glance at the label and either agree or disagree.
-Disagree by adding the `risk-dispute` label (never touched by the grader) plus a
-comment saying why — disputes are the pilot's calibration data.
+Nothing is gated, blocked, routed, or merged. Humans record a different
+assessment beside the computed label with `risk-dispute:R0` through
+`risk-dispute:R3`, or `/risk-dispute R2 [optional reason]`. The legacy
+`risk-dispute` label and `/risk-dispute [optional reason]` remain valid with no
+human tier. No dispute changes the computed `risk:R*`; both forms become
+calibration data.
 
 ## How a grade is computed
 
@@ -106,8 +108,8 @@ Two CI-specific mechanics worth knowing:
 
 Every grade above is triggered by a `pull_request` event. Two things need a grade
 with no event: a repo that **enrolls mid-stream** and wants the open queue it
-already has labeled, and a **manual re-grade** after a `.github/risk.json` change
-or on a PR carrying `risk-dispute`. Both are a `workflow_dispatch` on the
+already has labeled, and a **manual re-grade** after a `.github/risk.json` change.
+Both are a `workflow_dispatch` on the
 consumer's caller, forwarding a number:
 
 ```yaml
@@ -177,7 +179,7 @@ Operational caveats for a backfill:
   re-dispatch on `pr_number` if a final grade looks wrong. The residual it costs
   instead is narrower, but it cuts both ways: the PUT is built from a snapshot
   read, so a **non-owned** label added in the read→PUT window is dropped
-  (`risk-dispute` included — re-add a dispute that lands in that instant) and one
+  (`risk-dispute` forms included — re-add a dispute that lands in that instant) and one
   **removed** in that window is resurrected. The window opens only on a run that
   actually changes the grade, and is about one API round-trip — three on the
   first grade in a repo, where the label pre-create sits inside it. A drop is not
diff --git a/scripts/pr-risk/apply-risk-label.sh b/scripts/pr-risk/apply-risk-label.sh
index b413a6d..68a4b8e 100755
--- a/scripts/pr-risk/apply-risk-label.sh
+++ b/scripts/pr-risk/apply-risk-label.sh
@@ -16,13 +16,13 @@
 # up front if any tier maps to an empty name, so the array can never degrade to the empty-labels
 # request that strips a PR. Labels it does NOT own are carried through the PUT as the snapshot read
 # saw them (see RESIDUAL), so a human who disagrees with a grade records that with their
-# OWN label (the pilot convention is `risk-dispute`) and the grader will never fight it. Editing the
-# grader-owned label by hand is futile by design: the next push re-syncs it.
+# OWN label (`risk-dispute` or `risk-dispute:R0` .. `risk-dispute:R3`) and the grader will never
+# fight it. Editing the grader-owned label by hand is futile by design: the next push re-syncs it.
 #
 # RESIDUAL — the price of atomicity, worth knowing for the pilot: the PUT is built from a SNAPSHOT
 # read, so it is an unguarded read-modify-write (the labels endpoint offers no version precondition
 # that could make it otherwise), and it clobbers BOTH directions inside that window. A NON-owned
-# label ADDED there is silently dropped — `risk-dispute` INCLUDED — and a non-owned label REMOVED
+# label ADDED there is silently dropped — `risk-dispute` forms INCLUDED — and a non-owned label REMOVED
 # there is RESURRECTED, so a `do-not-merge` or review label a human or a sibling labeler cleared in
 # that instant comes back. The window opens ONLY on a run that actually changes the grade (an
 # in-sync PR writes nothing at all) and is normally ~one API round-trip; on the FIRST grade in a
diff --git a/scripts/pr-risk/handle-risk-dispute.sh b/scripts/pr-risk/handle-risk-dispute.sh
new file mode 100755
index 0000000..8e9ed7c
--- /dev/null
+++ b/scripts/pr-risk/handle-risk-dispute.sh
@@ -0,0 +1,316 @@
+#!/usr/bin/env bash
+
+set -uo pipefail
+
+REPO="${REPO:-}"
+PR_NUMBER="${PR_NUMBER:-}"
+RECORD="${RECORD:-}"
+EVENT_NAME="${EVENT_NAME:-}"
+EVENT_ACTION="${EVENT_ACTION:-}"
+EVENT_LABEL="${EVENT_LABEL:-}"
+COMMENT_BODY="${COMMENT_BODY:-}"
+COMMENT_ID="${COMMENT_ID:-}"
+COMMENT_URL="${COMMENT_URL:-}"
+ACTOR="${ACTOR:-}"
+ACTOR_ASSOCIATION="${ACTOR_ASSOCIATION:-}"
+ALLOWED_ASSOCIATIONS="${ALLOWED_ASSOCIATIONS:-OWNER,MEMBER,COLLABORATOR}"
+RUN_ID="${RUN_ID:-}"
+NOW="${NOW:-$(date -u +%Y-%m-%dT%H:%M:%SZ)}"
+DRY_RUN="${DRY_RUN:-0}"
+
+DISPUTE_LABEL="risk-dispute"
+DISPUTE_PREFIX="${DISPUTE_LABEL}:"
+DISPUTE_MARKER="ci-pr-risk-dispute:v1"
+
+log() { printf '[risk-dispute] %s\n' "$*" >&2; }
+die() { printf '[risk-dispute] ERROR %s\n' "$*" >&2; exit 2; }
+fail() { printf '[risk-dispute] FAIL %s\n' "$*" >&2; exit 4; }
+
+[ -n "$REPO" ] || die "REPO is required"
+[[ "$REPO" =~ ^[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+$ ]] || die "bad REPO '$REPO'"
+[[ "$PR_NUMBER" =~ ^[0-9]+$ ]] || die "bad PR_NUMBER '$PR_NUMBER'"
+command -v jq >/dev/null 2>&1 || die "jq not found on PATH"
+[ "$DRY_RUN" = 1 ] || command -v gh >/dev/null 2>&1 || die "gh not found on PATH"
+
+trim() {
+  sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//' <<<"$1"
+}
+
+action=""
+tier=""
+reason=""
+source=""
+bootstrap=0
+clear_scope="all"
+
+case "$EVENT_NAME:$EVENT_ACTION" in
+  issue_comment:created)
+    [[ "$ALLOWED_ASSOCIATIONS" != *[[:space:]]* ]] \
+      || die "ALLOWED_ASSOCIATIONS must be comma-separated with no spaces"
+    case ",$ALLOWED_ASSOCIATIONS," in
+      *",$ACTOR_ASSOCIATION,"*) ;;
+      *) log "ignoring /risk-dispute from association '${ACTOR_ASSOCIATION:-unknown}'"; exit 0 ;;
+    esac
+
+    body="${COMMENT_BODY//$'\r'/}"
+    first_line="${body%%$'\n'*}"
+    remaining=""
+    [[ "$body" != *$'\n'* ]] || remaining="${body#*$'\n'}"
+    if [[ "$first_line" =~ ^/risk-dispute[[:space:]]+(R[0-3])([[:space:]]+(.*))?$ ]]; then
+      action="set"
+      tier="${BASH_REMATCH[1]}"
+      reason="$(trim "${BASH_REMATCH[3]:-}")"
+      if [ -n "$(trim "$remaining")" ]; then
+        [ -z "$reason" ] || reason+=$'\n'
+        reason+="$(trim "$remaining")"
+      fi
+    elif [[ "$first_line" =~ ^/risk-dispute[[:space:]]+clear[[:space:]]*$ ]]; then
+      action="clear"
+    elif [[ "$first_line" =~ ^/risk-dispute([[:space:]]+(.*))?$ ]]; then
+      reason="$(trim "${BASH_REMATCH[2]:-}")"
+      [[ "$reason" =~ ^R[0-9]+([[:space:]]|$) ]] \
+        && die "bad tier; use R0, R1, R2 or R3"
+      if [ -n "$(trim "$remaining")" ]; then
+        [ -z "$reason" ] || reason+=$'\n'
+        reason+="$(trim "$remaining")"
+      fi
+      action="set"
+    else
+      die "bad command; use '/risk-dispute [optional reason]', '/risk-dispute R0..R3 [optional reason]' or '/risk-dispute clear'"
+    fi
+    source="comment"
+    ;;
+  pull_request:labeled)
+    if [[ "$EVENT_LABEL" =~ ^risk-dispute:(R[0-3])$ ]]; then
+      tier="${BASH_REMATCH[1]}"
+    elif [ "$EVENT_LABEL" != "$DISPUTE_LABEL" ]; then
+      exit 0
+    fi
+    action="set"
+    source="label"
+    ;;
+  pull_request:unlabeled)
+    if [[ "$EVENT_LABEL" =~ ^risk-dispute:(R[0-3])$ ]]; then
+      tier="${BASH_REMATCH[1]}"
+      clear_scope="tiered"
+    elif [ "$EVENT_LABEL" = "$DISPUTE_LABEL" ]; then
+      clear_scope="legacy"
+    else
+      exit 0
+    fi
+    action="clear"
+    source="label"
+    ;;
+  pull_request:opened|pull_request:reopened|pull_request:ready_for_review)
+    action="bootstrap"
+    source="workflow"
+    ;;
+  pull_request:synchronize)
+    action="expire"
+    source="push"
+    bootstrap=1
+    ;;
+  *) exit 0 ;;
+esac
+
+ERRF="$(mktemp "${TMPDIR:-/tmp}/risk-dispute-err.XXXXXX")" || die "mktemp failed"
+trap 'rm -f "$ERRF"' EXIT
+ghq() { gh "$@" 2>"$ERRF"; }
+gherr() { tr '\n' ' ' <"$ERRF" | sed 's/[[:space:]]*$//'; }
+enc() { jq -rn --arg s "$1" '$s | @uri'; }
+color_for() {
+  case "$1" in
+    R0) echo 0e8a16 ;; R1) echo fbca04 ;; R2) echo d93f0b ;; R3) echo b60205 ;;
+    *) echo cfd3d7 ;;
+  esac
+}
+
+description_for() {
+  if [ "$1" = legacy ]; then
+    echo "Human disagreement with PR risk grade; tier unspecified"
+  else
+    echo "Human PR risk assessment for grader calibration"
+  fi
+}
+
+ensure_dispute_labels() {
+  local labels candidate candidate_tier
+  labels="$(ghq api --paginate "repos/$REPO/labels?per_page=100" --jq '[.[].name]' \
+             | jq -sc 'add // []')" \
+    || fail "could not read repository labels on $REPO: $(gherr)"
+  for candidate_tier in legacy R0 R1 R2 R3; do
+    if [ "$candidate_tier" = legacy ]; then
+      candidate="$DISPUTE_LABEL"
+    else
+      candidate="${DISPUTE_PREFIX}${candidate_tier}"
+    fi
+    if jq -e --arg candidate "$candidate" \
+      'map(ascii_downcase) | index($candidate | ascii_downcase) != null' \
+      >/dev/null <<<"$labels"; then
+      continue
+    fi
+    [ "$DRY_RUN" = 1 ] && { log "DRY RUN — would create '$candidate'"; continue; }
+    ghq api -X POST "repos/$REPO/labels" -f name="$candidate" \
+      -f color="$(color_for "$candidate_tier")" \
+      -f description="$(description_for "$candidate_tier")" >/dev/null \
+      || fail "could not create '$candidate': $(gherr)"
+  done
+}
+
+if [ "$action" = bootstrap ] || [ "$bootstrap" = 1 ]; then
+  ensure_dispute_labels
+  [ "$action" != bootstrap ] || exit 0
+fi
+
+current="$(ghq api --paginate "repos/$REPO/issues/$PR_NUMBER/labels?per_page=100" --jq '[.[].name]' \
+           | jq -sc 'add // []')" \
+  || fail "could not read labels on $REPO#$PR_NUMBER: $(gherr)"
+
+disputes="$(jq -c '[.[] | select(test("^risk-dispute:R[0-3]$"; "i"))]' <<<"$current")" \
+  || fail "could not inspect dispute labels"
+dispute_count="$(jq 'length' <<<"$disputes")" || fail "could not count dispute labels"
+legacy_count="$(jq '[.[] | select(ascii_downcase == "risk-dispute")] | length' <<<"$current")" \
+  || fail "could not inspect the legacy dispute label"
+
+if [ "$action" = expire ] && [ "$dispute_count" -eq 0 ] && [ "$legacy_count" -eq 0 ]; then
+  exit 0
+fi
+
+if [ "$action" = set ]; then
+  if [ -n "$tier" ]; then
+    target="${DISPUTE_PREFIX}${tier}"
+    target_count="$(jq --arg target "$target" '[.[] | select(ascii_downcase == ($target | ascii_downcase))] | length' <<<"$disputes")" \
+      || fail "could not inspect the target dispute label"
+    needs_sync=0
+    [ "$dispute_count" -eq 1 ] && [ "$target_count" -eq 1 ] && [ "$legacy_count" -eq 0 ] \
+      || needs_sync=1
+  else
+    target="$DISPUTE_LABEL"
+    needs_sync=0
+    [ "$legacy_count" -eq 1 ] || needs_sync=1
+  fi
+  if [ "$needs_sync" = 1 ]; then
+    if [ "$DRY_RUN" != 1 ]; then
+      if ! probe_err="$(gh api "repos/$REPO/labels/$(enc "$target")" 2>&1 >/dev/null)"; then
+        case "$probe_err" in
+          *"HTTP 404"*|*"Not Found"*)
+            ghq api -X POST "repos/$REPO/labels" -f name="$target" \
+              -f color="$(color_for "$tier")" \
+              -f description="$(description_for "${tier:-legacy}")" >/dev/null \
+              || fail "could not create '$target': $(gherr)"
+            ;;
+          *) fail "could not inspect '$target': $(tr '\n' ' ' <<<"$probe_err")" ;;
+        esac
+      fi
+    fi
+    if [ -n "$tier" ]; then
+      desired="$(jq -c --arg target "$target" \
+        '[.[] | select(test("^risk-dispute(?::R[0-3])?$"; "i") | not)] + [$target]' <<<"$current")" \
+        || fail "could not build the tiered dispute label set"
+    else
+      desired="$(jq -c --arg target "$target" '. + [$target]' <<<"$current")" \
+        || fail "could not add the legacy dispute label"
+    fi
+  else
+    desired="$current"
+  fi
+else
+  case "$clear_scope" in
+    legacy)
+      desired="$(jq -c '[.[] | select(ascii_downcase != "risk-dispute")]' <<<"$current")" ;;
+    tiered)
+      desired="$(jq -c '[.[] | select(test("^risk-dispute:R[0-3]$"; "i") | not)]' <<<"$current")" ;;
+    *)
+      desired="$(jq -c '[.[] | select(test("^risk-dispute(?::R[0-3])?$"; "i") | not)]' <<<"$current")" ;;
+  esac || fail "could not clear dispute labels"
+fi
+
+if [ "$desired" != "$current" ]; then
+  if [ "$DRY_RUN" = 1 ]; then
+    log "DRY RUN — would sync dispute labels to $(jq -c . <<<"$desired")"
+  else
+    jq -n --argjson labels "$desired" '{labels:$labels}' \
+      | ghq api -X PUT "repos/$REPO/issues/$PR_NUMBER/labels" --input - >/dev/null \
+      || fail "could not sync dispute labels on $REPO#$PR_NUMBER: $(gherr)"
+  fi
+fi
+
+computed_tier=""
+map_version=""
+head_sha=""
+if [ -n "$RECORD" ] && [ -s "$RECORD" ] && jq -e . "$RECORD" >/dev/null 2>&1; then
+  computed_tier="$(jq -r '.risk.tier // ""' "$RECORD")"
+  map_version="$(jq -r '.risk.map_version // ""' "$RECORD")"
+  head_sha="$(jq -r '.head_sha // ""' "$RECORD")"
+fi
+[ -n "$computed_tier" ] || computed_tier="$(jq -r '[.[] | capture("^risk:(?<tier>R[0-3])$"; "i").tier | ascii_upcase][0] // ""' <<<"$current")"
+if [ -z "$head_sha" ]; then
+  head_sha="$(ghq api "repos/$REPO/pulls/$PR_NUMBER" --jq '.head.sha')" \
+    || fail "could not read the PR head: $(gherr)"
+fi
+
+previous_tiers="$(jq -c '[.[] | capture("^risk-dispute:(?<tier>R[0-3])$"; "i").tier | ascii_upcase]' <<<"$disputes")" \
+  || previous_tiers='[]'
+if [ -n "$tier" ] && [ "$EVENT_NAME:$EVENT_ACTION" = pull_request:labeled ]; then
+  previous_tiers="$(jq -c --arg tier "$tier" 'map(select(. != $tier))' <<<"$previous_tiers")" \
+    || fail "could not record the previous dispute tiers"
+elif [ -n "$tier" ] && [ "$EVENT_NAME:$EVENT_ACTION" = pull_request:unlabeled ]; then
+  previous_tiers="$(jq -c --arg tier "$tier" 'if index($tier) then . else . + [$tier] end' <<<"$previous_tiers")" \
+    || fail "could not record the previous dispute tiers"
+fi
+reason_json="null"
+[ -z "$reason" ] || reason_json="$(jq -cn --arg reason "$reason" '$reason')"
+human_json="null"
+if [ "$action" = set ] && [ -n "$tier" ]; then
+  human_json="$(jq -cn --arg tier "$tier" '$tier')"
+fi
+
+record="$(jq -cn \
+  --arg action "$action" --arg repo "$REPO" --argjson pr "$PR_NUMBER" \
+  --arg head_sha "$head_sha" --arg computed_tier "$computed_tier" \
+  --argjson human_tier "$human_json" --argjson previous_tiers "$previous_tiers" \
+  --argjson reason "$reason_json" --arg source "$source" --arg actor "$ACTOR" \
+  --arg association "$ACTOR_ASSOCIATION" --arg comment_id "$COMMENT_ID" \
+  --arg comment_url "$COMMENT_URL" --arg map_version "$map_version" \
+  --arg run_id "$RUN_ID" --arg created_at "$NOW" \
+  '{schema:1, action:$action, repo:$repo, pr:$pr, head_sha:$head_sha,
+    computed_tier:(if $computed_tier == "" then null else $computed_tier end),
+    human_tier:$human_tier, previous_tiers:$previous_tiers, reason:$reason,
+    source:$source, actor:(if $actor == "" then null else $actor end),
+    actor_association:(if $association == "" then null else $association end),
+    source_comment_id:(if $comment_id == "" then null else $comment_id end),
+    source_comment_url:(if $comment_url == "" then null else $comment_url end),
+    map_version:(if $map_version == "" then null else $map_version end),
+    run_id:(if $run_id == "" then null else $run_id end), created_at:$created_at}')" \
+  || fail "could not build the audit record"
+
+encoded="$(jq -rn --arg record "$record" '$record | @base64')" || fail "could not encode the audit record"
+case "$action" in
+  set)
+    if [ -n "$tier" ]; then
+      summary="Risk dispute recorded: grader \`${computed_tier:-unknown}\`, human \`${tier}\` on \`${head_sha:0:12}\`."
+    else
+      summary="Risk dispute recorded: grader \`${computed_tier:-unknown}\`, human tier unspecified on \`${head_sha:0:12}\`."
+    fi
+    ;;
+  clear) summary="Risk dispute cleared on \`${head_sha:0:12}\`." ;;
+  expire) summary="Risk dispute expired after a new push to \`${head_sha:0:12}\`." ;;
+esac
+if [ "$source" = comment ] && [ -n "$COMMENT_URL" ] && [ -n "$reason" ]; then
+  summary+=" Reason: [command comment]($COMMENT_URL)."
+elif [ "$action" = set ]; then
+  summary+=" No reason supplied."
+fi
+body="<!-- ${DISPUTE_MARKER} ${encoded} -->
+${summary}"
+
+if [ "$DRY_RUN" = 1 ]; then
+  printf '%s\n' "$body"
+  exit 0
+fi
+
+jq -n --arg body "$body" '{body:$body}' \
+  | ghq api -X POST "repos/$REPO/issues/$PR_NUMBER/comments" --input - >/dev/null \
+  || fail "could not write the dispute audit record: $(gherr)"
+
+log "$action recorded for $REPO#$PR_NUMBER"
diff --git a/scripts/pr-risk/publish-risk-surfaces.sh b/scripts/pr-risk/publish-risk-surfaces.sh
index efb8d03..6dd1035 100644
--- a/scripts/pr-risk/publish-risk-surfaces.sh
+++ b/scripts/pr-risk/publish-risk-surfaces.sh
@@ -70,10 +70,9 @@
 # overwritten, and the reviewer re-ticks — which is why the body is re-read by id IMMEDIATELY
 # before the write rather than reused from the paginated scan.
 #
-# `risk-grade-disputed` (this script's) is DELIBERATELY DISTINCT from `risk-dispute` (the human
-# convention the grader never touches). One is a machine-maintained mirror of a checkbox and is
-# rewritten on every grade; the other is a human's own label and would be fought over if this
-# script owned it.
+# `risk-grade-disputed` (this script's) is DELIBERATELY DISTINCT from the human-owned
+# `risk-dispute` and `risk-dispute:R*` assessment labels. This script mirrors a checkbox; it never
+# assigns a human tier.
 #
 # Inputs (env):
 #   REPO             owner/name of the repo holding the PR                          (required)
diff --git a/scripts/pr-risk/tests/test_apply_risk_label.sh b/scripts/pr-risk/tests/test_apply_risk_label.sh
index 78ab30f..4ba82a0 100755
--- a/scripts/pr-risk/tests/test_apply_risk_label.sh
+++ b/scripts/pr-risk/tests/test_apply_risk_label.sh
@@ -136,11 +136,11 @@ if grep -q -- '-X POST repos/test/repo/issues/7/labels' "$GH_LOG"; then
 else ok "and never an additive POST (that is the interleaving)"; fi
 
 echo "— unowned labels are preserved verbatim, disputes included —"
-: > "$GH_LOG"; printf 'risk:R1\nrisk-dispute\nbug\n' > "$CURRENT_LABELS"
+: > "$GH_LOG"; printf 'risk:R1\nrisk-dispute\nrisk-dispute:R2\nbug\n' > "$CURRENT_LABELS"
 PATH="$SANDBOX/bin:$PATH" REPO=test/repo PR_NUMBER=7 TIER=R3 bash "$SCRIPT" >/dev/null 2>&1
 put3="$(grep -- '-X PUT repos/test/repo/issues/7/labels ' "$GH_LOG")"
 eq "the PUT carries exactly the unowned labels plus the new target" \
-   "api -X PUT repos/test/repo/issues/7/labels -f labels[]=risk-dispute -f labels[]=bug -f labels[]=risk:R3" \
+   "api -X PUT repos/test/repo/issues/7/labels -f labels[]=risk-dispute -f labels[]=risk-dispute:R2 -f labels[]=bug -f labels[]=risk:R3" \
    "$put3"
 
 echo "— first use: the label is pre-created before the sync —"
@@ -233,7 +233,7 @@ echo "— a broken jq must fail the run, never degrade the PUT to target-only 
 # The carry-through filter used to run inside a process substitution, where its exit status is
 # structurally unobservable: `pipefail` does not reach `< <(...)` and `set -e` is off. A jq that
 # failed there appended nothing, so this destructive full-set replace silently became
-# `labels[]=$TARGET` alone — DELETING every unowned label on the PR (`risk-dispute` included)
+# `labels[]=$TARGET` alone — DELETING every unowned label on the PR (`risk-dispute` forms included)
 # while logging "synced" and exiting 0. A total replace must refuse to run on an unverified set.
 mkdir -p "$SANDBOX/binjqfail"
 cp "$SANDBOX/bin/gh" "$SANDBOX/binjqfail/gh"
@@ -244,7 +244,7 @@ for a in "$@"; do [ "$a" = --argjson ] && { echo 'jq: error: synthetic failure'
 exec "$REAL_JQ" "$@"
 STUB
 chmod +x "$SANDBOX/binjqfail/jq"
-: > "$GH_LOG"; printf 'risk:R0\nrisk-dispute\nkeep-me\n' > "$CURRENT_LABELS"
+: > "$GH_LOG"; printf 'risk:R0\nrisk-dispute\nrisk-dispute:R3\nkeep-me\n' > "$CURRENT_LABELS"
 REAL_JQ="$(command -v jq)" PATH="$SANDBOX/binjqfail:$PATH" \
   REPO=test/repo PR_NUMBER=7 TIER=R2 bash "$SCRIPT" >/dev/null 2>&1
 eq "a failing carry-through filter exits 4" 4 "$?"
diff --git a/scripts/pr-risk/tests/test_handle_risk_dispute.sh b/scripts/pr-risk/tests/test_handle_risk_dispute.sh
new file mode 100755
index 0000000..97fa40f
--- /dev/null
+++ b/scripts/pr-risk/tests/test_handle_risk_dispute.sh
@@ -0,0 +1,179 @@
+#!/usr/bin/env bash
+
+set -uo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+SCRIPT="$ROOT/handle-risk-dispute.sh"
+SANDBOX="$(mktemp -d)"
+trap 'rm -rf "$SANDBOX"' EXIT
+mkdir -p "$SANDBOX/bin"
+
+PASS=0
+FAIL=0
+ok() { PASS=$((PASS + 1)); printf 'ok - %s\n' "$1"; }
+bad() { FAIL=$((FAIL + 1)); printf 'not ok - %s: %s\n' "$1" "$2"; }
+eq() {
+  if [ "$2" = "$3" ]; then ok "$1"; else bad "$1" "want '$2', got '$3'"; fi
+}
+
+export GH_LOG="$SANDBOX/gh.log"
+export LABELS="$SANDBOX/labels.json"
+export LAST_PUT="$SANDBOX/put.json"
+export AUDIT="$SANDBOX/audit.json"
+export CREATED_LABELS="$SANDBOX/created-labels.txt"
+export HEAD_SHA="0123456789abcdef0123456789abcdef01234567"
+
+cat >"$SANDBOX/bin/gh" <<'STUB'
+#!/usr/bin/env bash
+printf '%s\n' "$*" >>"$GH_LOG"
+case "$*" in
+  *"issues/7/labels?per_page=100"*) cat "$LABELS" ;;
+  *"repos/test/repo/labels?per_page=100"*) printf '%s\n' '["risk-dispute:R0"]' ;;
+  *"repos/test/repo/labels/risk-dispute"*) echo '{}' ;;
+  *"-X PUT repos/test/repo/issues/7/labels"*) cat >"$LAST_PUT" ;;
+  *"-X POST repos/test/repo/issues/7/comments"*) cat >"$AUDIT" ;;
+  *"repos/test/repo/pulls/7"*) printf '%s\n' "$HEAD_SHA" ;;
+  *"-X POST repos/test/repo/labels"*) printf '%s\n' "$*" >>"$CREATED_LABELS" ;;
+  *) echo "unexpected gh call: $*" >&2; exit 1 ;;
+esac
+STUB
+chmod +x "$SANDBOX/bin/gh"
+
+cat >"$SANDBOX/record.json" <<EOF
+{"head_sha":"$HEAD_SHA","risk":{"tier":"R1","map_version":"test-map"}}
+EOF
+
+reset_case() {
+  : >"$GH_LOG"
+  rm -f "$LAST_PUT" "$AUDIT" "$CREATED_LABELS"
+}
+
+run_handler() {
+  PATH="$SANDBOX/bin:$PATH" REPO=test/repo PR_NUMBER=7 \
+    RECORD="$SANDBOX/record.json" NOW=2026-08-17T22:00:00Z RUN_ID=99 \
+    bash "$SCRIPT"
+}
+
+audit_record() {
+  jq -r '.body' "$AUDIT" | sed -n '1s/^<!-- ci-pr-risk-dispute:v1 \([^ ]*\) -->$/\1/p' \
+    | jq -Rr '@base64d | fromjson'
+}
+
+reset_case
+printf '%s\n' '["risk:R1","risk-dispute"]' >"$LABELS"
+EVENT_NAME=issue_comment EVENT_ACTION=created ACTOR=reviewer ACTOR_ASSOCIATION=MEMBER \
+  COMMENT_ID=55 COMMENT_URL=https://github.com/test/repo/pull/7#issuecomment-55 \
+  COMMENT_BODY=$'/risk-dispute R2 because tests only\nSecond line.' run_handler
+eq "comment adds the requested dispute label" true \
+  "$(jq -r '.labels | index("risk-dispute:R2") != null' "$LAST_PUT")"
+eq "comment preserves the computed label" true \
+  "$(jq -r '.labels | index("risk:R1") != null' "$LAST_PUT")"
+eq "a tiered comment replaces the legacy label" false \
+  "$(jq -r '.labels | index("risk-dispute") != null' "$LAST_PUT")"
+eq "comment records the human tier" R2 "$(audit_record | jq -r '.human_tier')"
+eq "comment records the optional reason" $'because tests only\nSecond line.' \
+  "$(audit_record | jq -r '.reason')"
+
+reset_case
+printf '%s\n' '["risk:R1"]' >"$LABELS"
+EVENT_NAME=issue_comment EVENT_ACTION=created ACTOR=reviewer ACTOR_ASSOCIATION=MEMBER \
+  COMMENT_BODY='/risk-dispute R3' run_handler
+eq "an empty reason is accepted" null "$(audit_record | jq -r '.reason')"
+
+reset_case
+printf '%s\n' '["risk:R1"]' >"$LABELS"
+EVENT_NAME=issue_comment EVENT_ACTION=created ACTOR=reviewer ACTOR_ASSOCIATION=MEMBER \
+  COMMENT_BODY=$'/risk-dispute Existing workflow\nMore context.' run_handler
+eq "a legacy comment adds the plain dispute label" \
+  '["risk:R1","risk-dispute"]' "$(jq -c '.labels' "$LAST_PUT")"
+eq "a legacy comment records no human tier" null \
+  "$(audit_record | jq -r '.human_tier')"
+eq "a legacy comment preserves its reason" $'Existing workflow\nMore context.' \
+  "$(audit_record | jq -r '.reason')"
+
+reset_case
+printf '%s\n' '["risk:R1"]' >"$LABELS"
+EVENT_NAME=issue_comment EVENT_ACTION=created ACTOR=reviewer ACTOR_ASSOCIATION=MEMBER \
+  COMMENT_BODY='/risk-dispute' run_handler
+eq "a bare legacy command is accepted" risk-dispute \
+  "$(jq -r '.labels[-1]' "$LAST_PUT")"
+eq "a bare legacy command needs no reason" null "$(audit_record | jq -r '.reason')"
+
+reset_case
+printf '%s\n' '["risk:R1","risk-dispute"]' >"$LABELS"
+EVENT_NAME=pull_request EVENT_ACTION=labeled EVENT_LABEL=risk-dispute ACTOR=reviewer \
+  run_handler
+rewrite=0
+[ ! -e "$LAST_PUT" ] || rewrite=1
+eq "the legacy label is accepted without rewriting labels" 0 "$rewrite"
+eq "the legacy label records no human tier" null "$(audit_record | jq -r '.human_tier')"
+
+reset_case
+printf '%s\n' '["risk:R1","risk-dispute","risk-dispute:R3","risk-dispute:R2"]' >"$LABELS"
+EVENT_NAME=pull_request EVENT_ACTION=labeled EVENT_LABEL=risk-dispute:R2 ACTOR=reviewer \
+  run_handler
+eq "a label replaces the previous dispute tier" \
+  '["risk:R1","risk-dispute:R2"]' "$(jq -c '.labels' "$LAST_PUT")"
+eq "label entry records no reason" null "$(audit_record | jq -r '.reason')"
+eq "label entry records its source" label "$(audit_record | jq -r '.source')"
+eq "label entry records only the tier that preceded it" '["R3"]' \
+  "$(audit_record | jq -c '.previous_tiers')"
+
+reset_case
+printf '%s\n' '["risk:R1","risk-dispute:R3"]' >"$LABELS"
+EVENT_NAME=pull_request EVENT_ACTION=unlabeled EVENT_LABEL=risk-dispute ACTOR=reviewer \
+  run_handler
+rewrite=0
+[ ! -e "$LAST_PUT" ] || rewrite=1
+eq "removing the legacy label preserves a tiered dispute" 0 "$rewrite"
+eq "legacy removal retains the tier in history" '["R3"]' \
+  "$(audit_record | jq -c '.previous_tiers')"
+
+reset_case
+printf '%s\n' '["risk:R1"]' >"$LABELS"
+EVENT_NAME=pull_request EVENT_ACTION=unlabeled EVENT_LABEL=risk-dispute:R2 ACTOR=reviewer \
+  run_handler
+rewrite=0
+[ ! -e "$LAST_PUT" ] || rewrite=1
+eq "removing an already-removed dispute needs no label rewrite" 0 "$rewrite"
+eq "label removal records no current human tier" null \
+  "$(audit_record | jq -r '.human_tier')"
+eq "label removal records the removed tier" '["R2"]' \
+  "$(audit_record | jq -c '.previous_tiers')"
+
+reset_case
+printf '%s\n' '["risk:R1","risk-dispute","risk-dispute:R2"]' >"$LABELS"
+EVENT_NAME=issue_comment EVENT_ACTION=created ACTOR=reviewer ACTOR_ASSOCIATION=MEMBER \
+  COMMENT_BODY='/risk-dispute clear' run_handler
+eq "clear removes the dispute without touching computed risk" \
+  '["risk:R1"]' "$(jq -c '.labels' "$LAST_PUT")"
+eq "clear is recorded" clear "$(audit_record | jq -r '.action')"
+
+reset_case
+printf '%s\n' '["risk:R1","risk-dispute","risk-dispute:R2"]' >"$LABELS"
+EVENT_NAME=pull_request EVENT_ACTION=synchronize ACTOR=author run_handler
+eq "a new push expires the dispute" '["risk:R1"]' "$(jq -c '.labels' "$LAST_PUT")"
+eq "expiry is recorded" expire "$(audit_record | jq -r '.action')"
+eq "synchronize provisions the remaining dispute labels" 4 \
+  "$(wc -l <"$CREATED_LABELS" | tr -d ' ')"
+
+reset_case
+printf '%s\n' '["risk:R1"]' >"$LABELS"
+EVENT_NAME=pull_request EVENT_ACTION=labeled EVENT_LABEL=area:testing ACTOR=reviewer \
+  run_handler
+eq "unrelated labels are ignored" 0 "$(wc -l <"$GH_LOG" | tr -d ' ')"
+
+reset_case
+printf '%s\n' '["risk:R1"]' >"$LABELS"
+EVENT_NAME=issue_comment EVENT_ACTION=created ACTOR=outsider ACTOR_ASSOCIATION=NONE \
+  COMMENT_BODY='/risk-dispute R2' run_handler
+eq "unauthorized comments are ignored" 0 "$(wc -l <"$GH_LOG" | tr -d ' ')"
+
+reset_case
+printf '%s\n' '["risk:R1"]' >"$LABELS"
+EVENT_NAME=issue_comment EVENT_ACTION=created ACTOR=reviewer ACTOR_ASSOCIATION=MEMBER \
+  COMMENT_BODY='/risk-dispute R4 unsupported tier' run_handler >/dev/null 2>&1
+eq "invalid commands fail validation" 2 "$?"
+
+printf '%s passed, %s failed\n' "$PASS" "$FAIL"
+[ "$FAIL" -eq 0 ]
diff --git a/scripts/pr-risk/tests/test_publish_risk_surfaces.sh b/scripts/pr-risk/tests/test_publish_risk_surfaces.sh
index e2b3f85..54d372d 100644
--- a/scripts/pr-risk/tests/test_publish_risk_surfaces.sh
+++ b/scripts/pr-risk/tests/test_publish_risk_surfaces.sh
@@ -94,7 +94,8 @@ else bad "CHECKED_RE matches the ticked line we render" "$(grep -F "$DISPUTE_TEX
 if grep -Eq "$CHECKED_RE" <<<"$body"; then bad "CHECKED_RE does NOT match an unticked line" "$body"
 else ok "CHECKED_RE does NOT match an unticked line"; fi
 has "$dbody" "$DISPUTE_LABEL" "the checkbox names the label it applies"
-hasnt "$dbody" "risk-dispute —" "…and never claims the human-owned risk-dispute label"
+hasnt "$dbody" "risk-dispute —" "…and never claims the legacy human dispute label"
+hasnt "$dbody" "risk-dispute:R" "…and never claims a human tier label"
 
 echo "— ADVERSARIAL FILENAME: a crafted path cannot forge a dispute or break the table —"
 # git permits `|`, backticks and newlines in a filename. Rendered raw, such a path breaks out of