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+// SPDX-License-Identifier: Apache-2.0
+; specs/claw/github_surface.t27 -- what the TRI CLAW GitHub App does with each GitHub API surface,
+; for .t27, and the token each job is allowed to mint (epic #9271).
+; Owner, 2026-10-18, translated: "I gave full access. Study the GitHub API and connect full
+; coverage and value for .t27." Measured the same day (GET /apps/tri-claw, updated_at
+; 2026-10-18T06:59:05Z): the App holds write on 40 repository permissions, all repositories of
+; the gHashTag user account (installation 167308749).
+; --
+; Full access is the grant, not the token. The private key lives in two places (the t27 Actions
+; secret CLAW_APP_PRIVATE_KEY and the reviewer bees' Keychain), so a token minted without a
+; scope from any t27 branch would carry administration, secrets and workflows write over every
+; repository. The law here: a job names the SURFACE it serves, the token carries exactly that
+; row's permission at that row's level (plus metadata read, which GitHub always adds), and a
+; surface that is not mintable mints nothing. The grant may stay wide; every token stays narrow.
+; --
+; Shape (same discipline as specs/claw/recipes.t27): one ROW PER SURFACE, parallel arrays,
+; alignment pinned by tests. STATUS decides whether a row ever reaches a token:
+; - S_LIVE / S_PLANNED: mintable. PLANNED rows are filed lanes; a row moves to LIVE in the PR
+;   that ships it.
+; - S_OWNER: mintable only on the owner's explicit yes for that run (repository rulesets bind
+;   every merge in a repository; that is the owner's call, never the loop's).
+; - S_ACTIONS: the surface is real but the App adds nothing -- GitHub Actions' own token or OIDC
+;   does it better (attestation signing needs the Actions OIDC token, not an App key).
+; - S_NEEDS_HOOK: the value arrives only as a webhook event; claw runs zero servers
+;   (specs/claw/service.t27), so these rows wait for a receiver and mint nothing until then.
+; - S_UNAVAILABLE: the account type blocks it (custom properties exist only on organizations;
+;   gHashTag is a user account).
+; - S_REFUSED: no .t27 value, and holding it widens what a leaked token can do.
+; The honest limit: this table records what each surface is FOR. It does not prove a workflow
+; passes the scope it names -- that is the job of the workflow's own reviewer, and of the lane
+; that ships each PLANNED row.
+; ASCII only (L3). phi^2 + 1/phi^2 = 3 | TRINITY
+
+module ClawGithubSurface;
+
+use claw::recipes;
+
+/// Row status.
+pub const S_PLANNED : u8 = 0;
+pub const S_LIVE : u8 = 1;
+pub const S_OWNER : u8 = 2;
+pub const S_ACTIONS : u8 = 3;
+pub const S_NEEDS_HOOK : u8 = 4;
+pub const S_UNAVAILABLE : u8 = 5;
+pub const S_REFUSED : u8 = 6;
+
+/// Permission level, as GitHub spells it: none < read < write.
+pub const L_NONE : u8 = 0;
+pub const L_READ : u8 = 1;
+pub const L_WRITE : u8 = 2;
+
+/// The App's id; a ruleset's required check pins integration_id to it, so no other actor can
+/// post a green claw/t27f.
+pub const APP_ID : u32 = 5166765;
+
+/// Row count of the table.
+pub const COUNT : u32 = 22;
+
+/// Surface slug; the lookup key for every column.
+pub const SURFACES : [22]str = [
+    "check-run", "check-annotations", "code-scanning-sarif", "pr-files", "pr-suggestions",
+    "spec-read", "autofix-commit", "cross-repo-dispatch", "t27f-preview", "findings-issues",
+    "dependency-snapshot", "required-check-ruleset", "attestations", "commit-statuses",
+    "check-run-buttons", "merge-queue", "custom-properties", "secrets", "workflows",
+    "administration-other", "codespaces-agents", "repo-creation-hooks",
+];
+
+/// The GitHub App permission the surface needs (GitHub's own key names).
+pub const PERMS : [22]str = [
+    "checks", "checks", "security_events", "pull_requests", "pull_requests",
+    "contents", "contents", "contents", "deployments", "issues",
+    "contents", "administration", "attestations", "statuses",
+    "checks", "merge_queues", "repository_custom_properties", "secrets", "workflows",
+    "administration", "codespaces", "repository_hooks",
+];
+
+/// The level the surface needs.
+pub const LEVELS : [22]u8 = [
+    L_WRITE, L_WRITE, L_WRITE, L_READ, L_WRITE,
+    L_READ, L_WRITE, L_WRITE, L_WRITE, L_WRITE,
+    L_WRITE, L_WRITE, L_WRITE, L_WRITE,
+    L_WRITE, L_READ, L_WRITE, L_WRITE, L_WRITE,
+    L_WRITE, L_WRITE, L_WRITE,
+];
+
+pub const STATUS : [22]u8 = [
+    S_PLANNED, S_PLANNED, S_PLANNED, S_PLANNED, S_PLANNED,
+    S_PLANNED, S_PLANNED, S_PLANNED, S_PLANNED, S_PLANNED,
+    S_PLANNED, S_OWNER, S_ACTIONS, S_REFUSED,
+    S_NEEDS_HOOK, S_NEEDS_HOOK, S_UNAVAILABLE, S_REFUSED, S_REFUSED,
+    S_REFUSED, S_REFUSED, S_REFUSED,
+];
+
+/// The REST endpoint (or webhook event) the surface is.
+pub const ENDPOINTS : [22]str = [
+    "POST /repos/{o}/{r}/check-runs",
+    "PATCH /repos/{o}/{r}/check-runs/{id}",
+    "POST /repos/{o}/{r}/code-scanning/sarifs",
+    "GET /repos/{o}/{r}/pulls/{n}/files",
+    "POST /repos/{o}/{r}/pulls/{n}/reviews",
+    "GET /repos/{o}/{r}/git/trees/{sha}",
+    "POST /repos/{o}/{r}/git/commits",
+    "POST /repos/{o}/{r}/dispatches",
+    "POST /repos/{o}/{r}/deployments",
+    "POST /repos/{o}/{r}/issues/{n}/sub_issues",
+    "POST /repos/{o}/{r}/dependency-graph/snapshots",
+    "POST /repos/{o}/{r}/rulesets",
+    "POST /repos/{o}/{r}/attestations",
+    "POST /repos/{o}/{r}/statuses/{sha}",
+    "event check_run.requested_action",
+    "event merge_group.checks_requested",
+    "PATCH /repos/{o}/{r}/properties/values",
+    "PUT /repos/{o}/{r}/actions/secrets/{name}",
+    "PUT /repos/{o}/{r}/contents/.github/workflows/{f}",
+    "PATCH /repos/{o}/{r}",
+    "POST /repos/{o}/{r}/codespaces",
+    "POST /repos/{o}/{r}/hooks",
+];
+
+/// What the surface is worth to .t27 -- or why it is not used.
+pub const VALUES : [22]str = [
+    "the claw/t27f verdict on the PR head, under the App's own identity",
+    "t27c diagnostics pinned to the .t27 line in the diff, at most 50 per call",
+    "vacuous tests and dead specs as alerts that persist across commits and close when fixed",
+    "which .t27 files a PR touches, so only those specs are checked",
+    "t27c fmt drift as one-click suggestion blocks; review event COMMENT, never APPROVE",
+    "the specs and seals at the PR head, read without a clone",
+    "regenerated gen/ and reseals as a bot commit; unlike GITHUB_TOKEN, an App push re-runs CI",
+    "a spec merge in t27 tells trinity to re-vendor the cards it copies",
+    "a View deployment button from the PR to the T27F diagram of its specs",
+    "per-spec findings filed as sub-issues of one epic, closed when the finding clears",
+    "a repository that vendors t27 specs shows t27 in its dependency graph",
+    "claw/t27f becomes required, pinned to the App id so nobody else can post its green",
+    "signing needs the Actions OIDC token; t27o-release already attests, the App adds nothing",
+    "a second, weaker channel for what check-run already says",
+    "Regenerate and Reseal buttons on the check; the event arrives only by webhook",
+    "a queued merge needs claw/t27f on the queue sha in minutes; a 10-minute poll stalls it",
+    "t27 coverage as a repository property; properties exist only on organization accounts",
+    "no .t27 value; a token holding it can plant a secret in any repository",
+    "workflow files are owner gate files under the own-language gate; a bot never writes them",
+    "settings, collaborators, deletion; only the ruleset row uses administration",
+    "no .t27 value",
+    "no .t27 value; widens what a leaked token can create or redirect",
+];
+
+/// The measured grant (GET /apps/tri-claw, 2026-10-18T06:59:05Z), for the permissions this
+/// table names. Re-measure and edit here when the owner changes the App.
+pub const GRANT_PERMS : [15]str = [
+    "checks", "security_events", "pull_requests", "contents", "deployments",
+    "issues", "administration", "attestations", "statuses", "merge_queues",
+    "repository_custom_properties", "secrets", "workflows", "codespaces", "repository_hooks",
+];
+
+pub const GRANT_LEVELS : [15]u8 = [
+    L_WRITE, L_WRITE, L_WRITE, L_WRITE, L_WRITE,
+    L_WRITE, L_WRITE, L_WRITE, L_WRITE, L_WRITE,
+    L_WRITE, L_WRITE, L_WRITE, L_WRITE, L_WRITE,
+];
+
+/// Row index of a surface; -1 when unknown. Fail closed: callers check before use.
+pub fn row_of(surface : str) -> i32 {
+    for i in 0..22 {
+        if recipes::str_eq(SURFACES[i], surface) { return (i) as i32; }
+    }
+    return -1;
+}
+
+/// Whether row i may ever reach a token. owner_yes is the owner's explicit yes for this run.
+pub fn row_mintable(i : usize, owner_yes : bool) -> bool {
+    const s = STATUS[i];
+    if (s == S_LIVE or s == S_PLANNED) { return true; }
+    if (s == S_OWNER and owner_yes) { return true; }
+    return false;
+}
+
+/// The permission a job serving `surface` mints; "" when unknown or not mintable.
+pub fn perm_of(surface : str, owner_yes : bool) -> str {
+    const r = row_of(surface);
+    if (r < 0) { return ""; }
+    if (row_mintable((r) as usize, owner_yes) == false) { return ""; }
+    return PERMS[(r) as usize];
+}
+
+/// The level a job serving `surface` mints; L_NONE when unknown or not mintable.
+pub fn level_of(surface : str, owner_yes : bool) -> u8 {
+    const r = row_of(surface);
+    if (r < 0) { return L_NONE; }
+    if (row_mintable((r) as usize, owner_yes) == false) { return L_NONE; }
+    return LEVELS[(r) as usize];
+}
+
+/// The highest level any mintable row asks for `perm`; L_NONE means no token ever carries it.
+pub fn mint_ceiling(perm : str, owner_yes : bool) -> u8 {
+    var best : u8 = L_NONE;
+    for i in 0..22 {
+        if (recipes::str_eq(PERMS[i], perm) and row_mintable(i, owner_yes)) {
+            if (LEVELS[i] > best) { best = LEVELS[i]; }
+        }
+    }
+    return best;
+}
+
+/// The level the App was measured to hold for `perm`; L_NONE when not granted.
+pub fn granted(perm : str) -> u8 {
+    for i in 0..15 {
+        if recipes::str_eq(GRANT_PERMS[i], perm) { return GRANT_LEVELS[i]; }
+    }
+    return L_NONE;
+}
+
+/// Every mintable row fits inside the measured grant: the App can actually mint what it plans.
+pub fn plan_fits_grant(owner_yes : bool) -> bool {
+    for i in 0..22 {
+        if (row_mintable(i, owner_yes)) {
+            if (LEVELS[i] > granted(PERMS[i])) { return false; }
+        }
+    }
+    return true;
+}
+
+/// How many granted permissions no token will ever use at their granted level -- the part of
+/// the grant that only widens a leak. The owner may narrow the App by exactly these.
+pub fn over_granted(owner_yes : bool) -> u32 {
+    var n : u32 = 0;
+    for i in 0..15 {
+        if (mint_ceiling(GRANT_PERMS[i], owner_yes) < GRANT_LEVELS[i]) { n += 1; }
+    }
+    return n;
+}
+
+/// Census by status.
+pub fn count_status(s : u8) -> u32 {
+    var n : u32 = 0;
+    for i in 0..22 {
+        if STATUS[i] == s { n += 1; }
+    }
+    return n;
+}
+
+/// Every row has surface, permission, endpoint and value.
+pub fn every_row_filled() -> bool {
+    for i in 0..22 {
+        if SURFACES[i] == "" { return false; }
+        if PERMS[i] == "" { return false; }
+        if ENDPOINTS[i] == "" { return false; }
+        if VALUES[i] == "" { return false; }
+    }
+    return true;
+}
+
+/// No surface appears twice among the first n rows.
+pub fn all_surfaces_unique(n : usize) -> bool {
+    var i : usize = 0;
+    while (i < n) {
+        var j : usize = i + 1;
+        while (j < n) {
+            if recipes::str_eq(SURFACES[i], SURFACES[j]) { return false; }
+            j += 1;
+        }
+        i += 1;
+    }
+    return true;
+}
+
+test surface_rows_are_filled_and_unique {
+    assert every_row_filled() == true;
+    assert all_surfaces_unique((COUNT) as usize) == true;
+}
+
+test surface_census_adds_up {
+    assert count_status(S_PLANNED) == 11;
+    assert count_status(S_LIVE) == 0;
+    assert count_status(S_OWNER) == 1;
+    assert count_status(S_ACTIONS) == 1;
+    assert count_status(S_NEEDS_HOOK) == 2;
+    assert count_status(S_UNAVAILABLE) == 1;
+    assert count_status(S_REFUSED) == 6;
+    var total : u32 = 0;
+    var s : u8 = 0;
+    while (s <= S_REFUSED) {
+        total += count_status(s);
+        s += 1;
+    }
+    assert total == COUNT;
+}
+
+test claw_t27f_job_mints_exactly_three_narrow_scopes {
+    // The rollout's claw/t27f job serves check-run, pr-files and spec-read.
+    assert recipes::str_eq(perm_of("check-run", false), "checks") == true;
+    assert level_of("check-run", false) == L_WRITE;
+    assert recipes::str_eq(perm_of("pr-files", false), "pull_requests") == true;
+    assert level_of("pr-files", false) == L_READ;
+    assert recipes::str_eq(perm_of("spec-read", false), "contents") == true;
+    assert level_of("spec-read", false) == L_READ;
+}
+
+test refused_permissions_never_reach_a_token {
+    // Even with the owner's yes: refusal is about value, not consent.
+    assert mint_ceiling("secrets", true) == L_NONE;
+    assert mint_ceiling("workflows", true) == L_NONE;
+    assert mint_ceiling("statuses", true) == L_NONE;
+    assert mint_ceiling("codespaces", true) == L_NONE;
+    assert mint_ceiling("repository_hooks", true) == L_NONE;
+    assert level_of("secrets", true) == L_NONE;
+    assert level_of("administration-other", true) == L_NONE;
+}
+
+test administration_only_with_the_owner_yes {
+    assert mint_ceiling("administration", false) == L_NONE;
+    assert level_of("required-check-ruleset", false) == L_NONE;
+    assert mint_ceiling("administration", true) == L_WRITE;
+    assert level_of("required-check-ruleset", true) == L_WRITE;
+    // The yes opens the ruleset row, never the other administration row.
+    assert level_of("administration-other", true) == L_NONE;
+}
+
+test hook_rows_mint_nothing_although_their_permission_is_minted_elsewhere {
+    // checks is write through check-run; the buttons row still mints nothing on its own.
+    assert mint_ceiling("checks", false) == L_WRITE;
+    assert level_of("check-run-buttons", false) == L_NONE;
+    assert mint_ceiling("merge_queues", true) == L_NONE;
+    assert level_of("custom-properties", true) == L_NONE;
+    assert level_of("attestations", true) == L_NONE;
+}
+
+test write_surfaces_that_carry_the_value {
+    assert mint_ceiling("security_events", false) == L_WRITE;
+    assert mint_ceiling("pull_requests", false) == L_WRITE;
+    assert mint_ceiling("contents", false) == L_WRITE;
+    assert mint_ceiling("deployments", false) == L_WRITE;
+    assert mint_ceiling("issues", false) == L_WRITE;
+}
+
+test unknown_surface_fails_closed {
+    assert row_of("no-such-surface") == -1;
+    assert recipes::str_eq(perm_of("no-such-surface", true), "") == true;
+    assert level_of("no-such-surface", true) == L_NONE;
+    assert granted("no_such_permission") == L_NONE;
+}
+
+test the_plan_fits_the_measured_grant {
+    assert plan_fits_grant(false) == true;
+    assert plan_fits_grant(true) == true;
+}
+
+test over_grant_is_counted_so_the_owner_can_narrow_it {
+    // statuses, attestations, merge_queues, repository_custom_properties, secrets, workflows,
+    // codespaces, repository_hooks -- and administration until the owner says yes.
+    assert over_granted(false) == 9;
+    assert over_granted(true) == 8;
+}