diff --git a/.agents/skills/beadboard-driver/scripts/bb-mail-shim.mjs b/.agents/skills/beadboard-driver/scripts/bb-mail-shim.mjs
new file mode 100644
index 0000000..ae405b1
--- /dev/null
+++ b/.agents/skills/beadboard-driver/scripts/bb-mail-shim.mjs
@@ -0,0 +1,135 @@
+#!/usr/bin/env node
+/**
+ * bb-mail-shim.mjs
+ * Translates bd mail delegate calls into bb agent coordination commands.
+ *
+ * bd mail delegates by prepending the configured delegate string to all args:
+ *   `bd mail inbox` → `node bb-mail-shim.mjs inbox`
+ *   `bd mail send --to foo ...` → `node bb-mail-shim.mjs send --to foo ...`
+ *
+ * Agent identity is read from (in order):
+ *   1. BB_AGENT env var  (e.g., export BB_AGENT=silver-scribe)
+ *   2. BD_ACTOR env var  (git actor name used by bd commands)
+ *
+ * Command mappings:
+ *   bd mail inbox [--state s] [--bead b] [--limit n]
+ *     → bb agent inbox --agent <self> [...]
+ *
+ *   bd mail send --to <agent> --bead <id> --category <cat> --subject <s> --body <b>
+ *     → bb agent send --from <self> --to <agent> --bead <id> --category <cat> --subject <s> --body <b>
+ *     (--from injected automatically; omitted if caller already supplies it)
+ *
+ *   bd mail read <message-id>
+ *     → bb agent read --agent <self> --message <message-id>
+ *
+ *   bd mail ack <message-id>
+ *     → bb agent ack --agent <self> --message <message-id>
+ *
+ *   bd mail <other> [...]   (passthrough)
+ *     → bb agent <other> [...]
+ *
+ * To configure (one-time, or via session-preflight.mjs):
+ *   bd config set mail.delegate "node /abs/path/to/bb-mail-shim.mjs"
+ *
+ * Note: bb agent commands must be available globally (installed via izs.2).
+ * Until then, call tools/bb.ts from the BeadBoard repo directly.
+ */
+import { spawnSync } from 'node:child_process';
+
+function getAgentName() {
+  const agent = (process.env.BB_AGENT || process.env.BD_ACTOR || '').trim();
+  if (!agent) {
+    console.error(
+      'bb-mail-shim: agent identity required.\n' +
+        'Set BB_AGENT to your agent name before using bd mail:\n' +
+        '  export BB_AGENT=silver-scribe\n' +
+        'Or ensure BD_ACTOR is set by your bd environment.',
+    );
+    process.exit(1);
+  }
+  return agent;
+}
+
+function runBbAgent(args) {
+  const result = spawnSync('bb', ['agent', ...args], { stdio: 'inherit', shell: false });
+  if (result.error) {
+    if (result.error.code === 'ENOENT') {
+      console.error(
+        'bb-mail-shim: bb command not found in PATH.\n' +
+          'Install the BeadBoard global CLI so bb agent commands are available.\n' +
+          'Interim: call tools/bb.ts directly from the BeadBoard repo:\n' +
+          '  node --import tsx /path/to/beadboard/tools/bb.ts agent inbox --agent $BB_AGENT',
+      );
+    } else {
+      console.error(`bb-mail-shim: failed to spawn bb: ${result.error.message}`);
+    }
+    process.exit(1);
+  }
+  process.exit(result.status ?? 0);
+}
+
+const args = process.argv.slice(2);
+const subcommand = args[0];
+
+if (!subcommand || subcommand === '--help' || subcommand === '-h') {
+  console.log(`bb-mail-shim: bd mail → bb agent translation shim
+
+Usage (via bd mail after delegate is configured):
+  bd mail inbox [--state unread|read|acked] [--bead <id>] [--limit <n>]
+  bd mail send --to <agent> --bead <id> --category HANDOFF|BLOCKED|DECISION|INFO --subject <text> --body <text>
+  bd mail read <message-id>
+  bd mail ack <message-id>
+
+Requires: BB_AGENT or BD_ACTOR env var set to your agent name.
+
+Configure once per project:
+  bd config set mail.delegate "node /abs/path/to/bb-mail-shim.mjs"
+  # or run session-preflight.mjs which sets this automatically`);
+  process.exit(0);
+}
+
+const agent = getAgentName();
+
+switch (subcommand) {
+  case 'inbox': {
+    // bd mail inbox [...] → bb agent inbox --agent <self> [...]
+    runBbAgent(['inbox', '--agent', agent, ...args.slice(1)]);
+    break;
+  }
+
+  case 'send': {
+    // bd mail send [...] → bb agent send --from <self> [...]
+    // Inject --from only if caller hasn't already supplied it
+    const rest = args.slice(1);
+    const hasFrom = rest.includes('--from');
+    runBbAgent(['send', ...(hasFrom ? [] : ['--from', agent]), ...rest]);
+    break;
+  }
+
+  case 'read': {
+    // bd mail read <msg-id> [...] → bb agent read --agent <self> --message <msg-id> [...]
+    const msgId = args[1];
+    if (!msgId) {
+      console.error('bb-mail-shim: "read" requires a <message-id> argument');
+      process.exit(1);
+    }
+    runBbAgent(['read', '--agent', agent, '--message', msgId, ...args.slice(2)]);
+    break;
+  }
+
+  case 'ack': {
+    // bd mail ack <msg-id> [...] → bb agent ack --agent <self> --message <msg-id> [...]
+    const msgId = args[1];
+    if (!msgId) {
+      console.error('bb-mail-shim: "ack" requires a <message-id> argument');
+      process.exit(1);
+    }
+    runBbAgent(['ack', '--agent', agent, '--message', msgId, ...args.slice(2)]);
+    break;
+  }
+
+  default: {
+    // Passthrough for any other subcommand
+    runBbAgent([subcommand, ...args.slice(1)]);
+  }
+}
diff --git a/.agents/skills/beadboard-driver/scripts/session-preflight.mjs b/.agents/skills/beadboard-driver/scripts/session-preflight.mjs
index 2bb3e54..93945bc 100644
--- a/.agents/skills/beadboard-driver/scripts/session-preflight.mjs
+++ b/.agents/skills/beadboard-driver/scripts/session-preflight.mjs
@@ -1,8 +1,56 @@
 #!/usr/bin/env node
 
+import { spawnSync } from 'node:child_process';
+import { existsSync } from 'node:fs';
+import { fileURLToPath } from 'node:url';
+import { dirname, join } from 'node:path';
+
 import { findCommandInPath, resolveBbPath } from './lib/driver-lib.mjs';
 
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+/**
+ * Configures bd mail delegate to use bb-mail-shim.mjs.
+ * Runs `bd config set mail.delegate "node <shim-path>"` in the current directory.
+ *
+ * @param {string} bdPath - Resolved path to the bd binary.
+ * @param {string} shimPath - Absolute path to bb-mail-shim.mjs.
+ * @returns {object} Mail delegate config result.
+ */
+function configureMailDelegate(bdPath, shimPath) {
+  if (!existsSync(shimPath)) {
+    return {
+      configured: false,
+      reason: `shim not found at ${shimPath} — skill installation may be incomplete`,
+    };
+  }
+
+  const delegateCmd = `node ${shimPath}`;
+  const result = spawnSync(bdPath, ['config', 'set', 'mail.delegate', delegateCmd], {
+    stdio: 'pipe',
+    shell: false,
+  });
+
+  if (result.status !== 0) {
+    const stderr = result.stderr?.toString().trim() || '';
+    return {
+      configured: false,
+      reason: `bd config set failed: ${stderr || 'non-zero exit'}`,
+      delegate: delegateCmd,
+    };
+  }
+
+  return {
+    configured: true,
+    delegate: delegateCmd,
+    shim_path: shimPath,
+    note: 'Set BB_AGENT env var to your agent name before calling bd mail (e.g., export BB_AGENT=silver-scribe)',
+  };
+}
+
 async function main() {
+  const shimPath = join(__dirname, 'bb-mail-shim.mjs');
+
   try {
     const bdPath = await findCommandInPath('bd');
     if (!bdPath) {
@@ -17,6 +65,7 @@ async function main() {
               bd: { available: false, path: null },
             },
             bb: null,
+            mail: null,
           },
           null,
           2,
@@ -38,6 +87,10 @@ async function main() {
               bd: { available: true, path: bdPath },
             },
             bb,
+            mail: {
+              configured: false,
+              reason: 'bb not available — mail delegate requires bb agent commands (see izs.2)',
+            },
           },
           null,
           2,
@@ -46,6 +99,8 @@ async function main() {
       return;
     }
 
+    const mail = configureMailDelegate(bdPath, shimPath);
+
     process.stdout.write(
       `${JSON.stringify(
         {
@@ -55,6 +110,7 @@ async function main() {
             bd: { available: true, path: bdPath },
           },
           bb,
+          mail,
         },
         null,
         2,
@@ -67,11 +123,12 @@ async function main() {
           ok: false,
           error_code: 'PREFLIGHT_INTERNAL_ERROR',
           reason: error instanceof Error ? error.message : String(error),
-          remediation: 'Inspect session-preflight.js and retry.',
+          remediation: 'Inspect session-preflight.mjs and retry.',
           tools: {
             bd: { available: false, path: null },
           },
           bb: null,
+          mail: null,
         },
         null,
         2,