diff --git a/src/lib.mjs b/src/lib.mjs
index d78c164..81b770f 100644
--- a/src/lib.mjs
+++ b/src/lib.mjs
@@ -23,13 +23,51 @@ import { getRoster as _getRoster } from './roster.mjs';
 import { queryLocks as _queryLocks, publishLock as _publishLock, parseLockEvent } from './lock-ops.mjs';
 import { cmdDashboard } from './dashboard.mjs';
 import { ExitError } from './errors.mjs';
-import { todayDateStr, nowUnix } from './utils.mjs';
+import { todayDateStr, nowUnix, getIsoWeekStr } from './utils.mjs';
+import fs from 'node:fs/promises';
+import path from 'node:path';
 
 useWebSocketImplementation(WebSocket);
 
 // Re-export for backward compatibility/library usage
 export { parseLockEvent, cmdDashboard, _queryLocks as queryLocks, _publishLock as publishLock };
 
+async function getCompletedAgents(cadence, logDir, deps) {
+  const { readdir = fs.readdir, getDateStr = todayDateStr, getIsoWeek = getIsoWeekStr } = deps;
+  const completed = new Set();
+  const targetDir = path.join(logDir, cadence);
+
+  try {
+    const files = await readdir(targetDir);
+    const today = getDateStr();
+    const currentWeek = getIsoWeek();
+
+    for (const file of files) {
+      // Format: YYYY-MM-DDTHH-mm-ssZ__<agent>__<status>.md
+      const match = file.match(/^(\d{4}-\d{2}-\d{2})T.*__([a-zA-Z0-9-_]+)__(.*)\.md$/);
+      if (!match) continue;
+
+      const [_, datePart, agent, status] = match;
+
+      if (status === 'completed') {
+        if (cadence === 'daily' && datePart === today) {
+          completed.add(agent);
+        } else if (cadence === 'weekly') {
+          const fileWeek = getIsoWeek(datePart); // datePart is YYYY-MM-DD
+          if (fileWeek === currentWeek) {
+            completed.add(agent);
+          }
+        }
+      }
+    }
+  } catch (err) {
+    if (err.code !== 'ENOENT') {
+      console.error(`Warning: Failed to read log dir ${targetDir}: ${err.message}`);
+    }
+  }
+
+  return completed;
+}
 
 export async function cmdCheck(cadence, deps = {}) {
   const {
@@ -40,7 +78,9 @@ export async function cmdCheck(cadence, deps = {}) {
     getRoster = _getRoster,
     getDateStr = todayDateStr,
     log = console.log,
-    error = console.error
+    error = console.error,
+    logDir = 'task-logs',
+    ignoreLogs = false,
   } = deps;
 
   const relays = getRelays();
@@ -55,12 +95,20 @@ export async function cmdCheck(cadence, deps = {}) {
     error(`Paused agents: ${pausedAgents.join(', ')}`);
   }
 
+  let completedAgents = new Set();
+  if (!ignoreLogs) {
+    completedAgents = await getCompletedAgents(cadence, logDir, deps);
+    if (completedAgents.size > 0) {
+      error(`Completed agents (logs): ${[...completedAgents].join(', ')}`);
+    }
+  }
+
   const locks = await queryLocks(relays, cadence, dateStr, namespace);
   const lockedAgents = [...new Set(locks.map((l) => l.agent).filter(Boolean))];
   const roster = getRoster(cadence);
   const rosterSet = new Set(roster);
 
-  const excludedAgentsSet = new Set([...lockedAgents, ...pausedAgents]);
+  const excludedAgentsSet = new Set([...lockedAgents, ...pausedAgents, ...completedAgents]);
   const excludedAgents = [...excludedAgentsSet];
   const unknownLockedAgents = lockedAgents.filter((agent) => !rosterSet.has(agent));
   const available = roster.filter((a) => !excludedAgentsSet.has(a));
@@ -71,6 +119,7 @@ export async function cmdCheck(cadence, deps = {}) {
     date: dateStr,
     locked: lockedAgents.sort(),
     paused: pausedAgents.sort(),
+    completed: [...completedAgents].sort(),
     excluded: excludedAgents.sort(),
     available: available.sort(),
     lockCount: locks.length,
@@ -280,7 +329,16 @@ export async function cmdList(cadence, deps = {}) {
 
 
 function parseArgs(argv) {
-  const args = { command: null, agent: null, cadence: null, dryRun: false, force: false, port: DEFAULT_DASHBOARD_PORT };
+  const args = {
+    command: null,
+    agent: null,
+    cadence: null,
+    dryRun: false,
+    force: false,
+    port: DEFAULT_DASHBOARD_PORT,
+    logDir: 'task-logs',
+    ignoreLogs: false,
+  };
   let i = 0;
 
   if (argv.length > 0 && !argv[0].startsWith('-')) {
@@ -304,6 +362,10 @@ function parseArgs(argv) {
       args.force = true;
     } else if (arg === '--port') {
       args.port = parseInt(argv[++i], 10) || DEFAULT_DASHBOARD_PORT;
+    } else if (arg === '--log-dir') {
+      args.logDir = argv[++i];
+    } else if (arg === '--ignore-logs') {
+      args.ignoreLogs = true;
     }
   }
 
@@ -322,8 +384,10 @@ Commands:
   update [--force]                                 Update torch/ configuration (backups, merges)
 
 Options:
-  --dry-run   Build and sign the event but do not publish
-  --force     Overwrite existing files (for init) or all files (for update)
+  --dry-run       Build and sign the event but do not publish
+  --force         Overwrite existing files (for init) or all files (for update)
+  --log-dir       Path to task logs directory (default: task-logs)
+  --ignore-logs   Skip checking local logs for completed tasks
 
 Environment:
   NOSTR_LOCK_NAMESPACE      Namespace prefix for lock tags (default: torch)
@@ -357,7 +421,7 @@ export async function main(argv) {
           console.error(`ERROR: --cadence <${[...VALID_CADENCES].join('|')}> is required for check`);
           throw new ExitError(1, 'Missing cadence');
         }
-        await cmdCheck(args.cadence);
+        await cmdCheck(args.cadence, { logDir: args.logDir, ignoreLogs: args.ignoreLogs });
         break;
       }
 
diff --git a/src/utils.mjs b/src/utils.mjs
index f1a5f15..0538a3e 100644
--- a/src/utils.mjs
+++ b/src/utils.mjs
@@ -5,3 +5,25 @@ export function todayDateStr() {
 export function nowUnix() {
   return Math.floor(Date.now() / 1000);
 }
+
+export function getIsoWeekStr(dateInput) {
+  // Parse input to ensure we work with a Date object
+  // If dateInput is YYYY-MM-DD string, new Date() treats it as UTC.
+  const d = dateInput ? new Date(dateInput) : new Date();
+
+  // If valid date, use UTC components to avoid local timezone issues
+  if (isNaN(d.getTime())) return '';
+
+  // Copy date so we don't mutate the original if passed by reference (though new Date() handles that)
+  const date = new Date(Date.UTC(d.getUTCFullYear(), d.getUTCMonth(), d.getUTCDate()));
+
+  // ISO week date system: Thursday determines the year
+  // day: 0 (Sun) -> 6 (Sat). We want 1 (Mon) -> 7 (Sun)
+  const day = date.getUTCDay() || 7;
+  date.setUTCDate(date.getUTCDate() + 4 - day);
+
+  const yearStart = new Date(Date.UTC(date.getUTCFullYear(), 0, 1));
+  const weekNo = Math.ceil((((date - yearStart) / 86400000) + 1) / 7);
+
+  return `${date.getUTCFullYear()}-W${String(weekNo).padStart(2, '0')}`;
+}
diff --git a/test/lib.test.mjs b/test/lib.test.mjs
index de8dab5..ab0723c 100644
--- a/test/lib.test.mjs
+++ b/test/lib.test.mjs
@@ -25,6 +25,7 @@ describe('src/lib.mjs', () => {
     getDateStr: () => mockDateStr,
     log: mockLog,
     error: mockError,
+    readdir: async () => [],
   };
 
   beforeEach(() => {
diff --git a/test/scheduler-ratchet.test.mjs b/test/scheduler-ratchet.test.mjs
new file mode 100644
index 0000000..e981f4b
--- /dev/null
+++ b/test/scheduler-ratchet.test.mjs
@@ -0,0 +1,122 @@
+import { describe, it } from 'node:test';
+import assert from 'node:assert';
+import { cmdCheck } from '../src/lib.mjs';
+
+describe('Scheduler Ratchet Logic (Log Checking)', () => {
+  const mockRelays = ['wss://relay.test'];
+  const mockNamespace = 'test-ns';
+  const mockTtl = 3600;
+  const mockRoster = ['agentA', 'agentB', 'agentC'];
+  const mockDateStr = '2023-10-27'; // A Friday
+  const mockIsoWeekStr = '2023-W43';
+
+  // Base dependencies for cmdCheck
+  const baseDeps = {
+    getRelays: () => mockRelays,
+    getNamespace: () => mockNamespace,
+    getTtl: () => mockTtl,
+    getRoster: () => mockRoster,
+    loadTorchConfig: () => ({ scheduler: { paused: { daily: [], weekly: [] } } }),
+    getDateStr: () => mockDateStr,
+    getIsoWeek: () => mockIsoWeekStr,
+    queryLocks: async () => [], // No active locks by default
+    log: () => {},
+    error: () => {},
+    // Default readdir mock: returns empty array
+    readdir: async () => [],
+    logDir: 'mock-logs',
+  };
+
+  it('excludes agents completed today (daily)', async () => {
+    const deps = {
+      ...baseDeps,
+      readdir: async () => [
+        '2023-10-27T10-00-00Z__agentA__completed.md', // Matching date
+        '2023-10-26T10-00-00Z__agentB__completed.md', // Old date
+        '2023-10-27T12-00-00Z__agentC__failed.md',    // Failed today
+      ],
+    };
+
+    const result = await cmdCheck('daily', deps);
+
+    assert.deepStrictEqual(result.completed, ['agentA']);
+    assert.ok(result.excluded.includes('agentA'));
+    assert.ok(!result.excluded.includes('agentB')); // Completed yesterday, not excluded today
+    assert.ok(!result.excluded.includes('agentC')); // Failed, not excluded
+    assert.deepStrictEqual(result.available, ['agentB', 'agentC']);
+  });
+
+  it('excludes agents completed this week (weekly)', async () => {
+    const deps = {
+      ...baseDeps,
+      getIsoWeek: (date) => {
+          if (!date) return mockIsoWeekStr;
+          // Mock simple week logic: 2023-10-23 to 2023-10-29 is W43
+          if (date >= '2023-10-23' && date <= '2023-10-29') return '2023-W43';
+          return '2023-W42';
+      },
+      readdir: async () => [
+        '2023-10-23T10-00-00Z__agentA__completed.md', // Monday (in week)
+        '2023-10-20T10-00-00Z__agentB__completed.md', // Last week
+      ],
+    };
+
+    const result = await cmdCheck('weekly', deps);
+
+    assert.deepStrictEqual(result.completed, ['agentA']);
+    assert.ok(result.excluded.includes('agentA'));
+    assert.ok(!result.excluded.includes('agentB'));
+    assert.deepStrictEqual(result.available, ['agentB', 'agentC']);
+  });
+
+  it('combines locked and completed agents in exclusion list', async () => {
+    const deps = {
+      ...baseDeps,
+      queryLocks: async () => [{ agent: 'agentB', eventId: 'ev1' }], // agentB is locked
+      readdir: async () => [
+        '2023-10-27T10-00-00Z__agentA__completed.md', // agentA is completed
+      ],
+    };
+
+    const result = await cmdCheck('daily', deps);
+
+    assert.deepStrictEqual(result.completed, ['agentA']);
+    assert.deepStrictEqual(result.locked, ['agentB']);
+
+    // agentA (completed) and agentB (locked) should be excluded
+    assert.ok(result.excluded.includes('agentA'));
+    assert.ok(result.excluded.includes('agentB'));
+    assert.deepStrictEqual(result.available, ['agentC']);
+  });
+
+  it('ignores logs when --ignore-logs is set', async () => {
+    const deps = {
+      ...baseDeps,
+      readdir: async () => [
+        '2023-10-27T10-00-00Z__agentA__completed.md',
+      ],
+      ignoreLogs: true,
+    };
+
+    const result = await cmdCheck('daily', deps);
+
+    assert.deepStrictEqual(result.completed, []);
+    assert.ok(!result.excluded.includes('agentA'));
+    assert.deepStrictEqual(result.available, ['agentA', 'agentB', 'agentC']);
+  });
+
+  it('handles missing log directory gracefully', async () => {
+    const deps = {
+      ...baseDeps,
+      readdir: async () => {
+        const err = new Error('ENOENT');
+        err.code = 'ENOENT';
+        throw err;
+      },
+    };
+
+    const result = await cmdCheck('daily', deps);
+    assert.deepStrictEqual(result.completed, []);
+    assert.deepStrictEqual(result.available, ['agentA', 'agentB', 'agentC']);
+  });
+});
diff --git a/test/utils.test.mjs b/test/utils.test.mjs
new file mode 100644
index 0000000..06b2b94
--- /dev/null
+++ b/test/utils.test.mjs
@@ -0,0 +1,36 @@
+import { describe, it } from 'node:test';
+import assert from 'node:assert';
+import { getIsoWeekStr } from '../src/utils.mjs';
+
+describe('Date Utilities', () => {
+  describe('getIsoWeekStr', () => {
+    it('returns correct ISO week for simple cases', () => {
+      assert.strictEqual(getIsoWeekStr('2023-01-02'), '2023-W01'); // Mon
+      assert.strictEqual(getIsoWeekStr('2023-01-08'), '2023-W01'); // Sun
+      assert.strictEqual(getIsoWeekStr('2023-01-09'), '2023-W02'); // Mon
+    });
+
+    it('handles year boundaries correctly', () => {
+      // 2023-01-01 is Sunday. Belong to last week of 2022.
+      assert.strictEqual(getIsoWeekStr('2023-01-01'), '2022-W52');
+      // 2024-01-01 is Monday. Week 1 of 2024.
+      assert.strictEqual(getIsoWeekStr('2024-01-01'), '2024-W01');
+      // 2023-12-31 is Sunday. Week 52 of 2023.
+      assert.strictEqual(getIsoWeekStr('2023-12-31'), '2023-W52');
+    });
+
+    it('handles leap years', () => {
+      assert.strictEqual(getIsoWeekStr('2024-02-29'), '2024-W09');
+    });
+
+    it('handles empty input (defaults to today)', () => {
+      // Just check it returns a string in correct format
+      const result = getIsoWeekStr();
+      assert.match(result, /^\d{4}-W\d{2}$/);
+    });
+
+    it('handles invalid input gracefully', () => {
+      assert.strictEqual(getIsoWeekStr('invalid-date'), '');
+    });
+  });
+});