{"version":"2.1.280","anchor":"plugin-hooks-can-intercept-and-readdress-sendmessage-sends","canonical_anchor":"new-cross-sessionagent-messaging-plugin-api-sessionsend","heading":"Cross-session messaging gains hook interception and a new plugin API","tier":"use","area":"Plugins","scope":null,"heads_up":null,"url":"https:\/\/changelogs.core-directive.com\/v\/2.1.280\/e\/plugin-hooks-can-intercept-and-readdress-sendmessage-sends","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.280","markdown":"### Cross-session messaging gains hook interception and a new plugin API\n\nPlugins can now intercept and redirect messages sent between sessions, and gain a new API to read, send, and authorize cross-session messages\n\n**What**\n\n- `SendMessage` now routes through a hook pipeline that lets a plugin hook rewrite the recipient or the message text before delivery. If the recipient changes, permissions are re-checked. If a hook tries to readdress a send but no `ask` handler is present to approve it, or the readdress is denied, the send is dropped with an explicit refusal.\n\n- A new plugin-facing API was added for cross-session\/agent messaging: `$.session.messages` reads another agent's or session's transcript, `$.session.authorize` authorizes a first-party credential for a session, and `$.session.send` sends a message to another live session or agent (built on the `SendMessage` tool), including resolving session IDs and reporting delivery-failure reasons.\n\n**Why**\n\nTogether these give plugins more control and visibility over cross-session communication: they can intercept, redirect, or block messages between sessions, and they gain a proper API surface to read another session's history and send it messages programmatically, rather than only through the built-in tool.\n\n- Area: Plugins\n- Names: `SendMessage`\n- Tier: Use it now\n- Useful: 4\/5\n- Signal: 3\/5"}