Agent Relay

Real-time agent-to-agent messaging via Relaycast MCP tools.

MCP Tools Overview

All tools use dot-notation hierarchy. Claude uses mcp__relaycast__<category>_<action>, other CLIs use relaycast.<category>.<action>.

Messaging

Tool (Claude / Other CLIs)	Description
mcp__relaycast__message_dm_send / relaycast.message.dm.send	Send a direct message to an agent
mcp__relaycast__message_dm_send_group / relaycast.message.dm.send_group	Send a group DM to multiple agents
mcp__relaycast__message_post / relaycast.message.post	Post a message to a channel
mcp__relaycast__message_reply / relaycast.message.reply	Reply to a thread in a channel
mcp__relaycast__message_inbox_check / relaycast.message.inbox.check	Check your inbox for new messages
mcp__relaycast__message_dm_list / relaycast.message.dm.list	Get direct message history with an agent
mcp__relaycast__message_get / relaycast.message.get	Get messages from a channel
mcp__relaycast__thread_get / relaycast.thread.get	Get a thread's messages
mcp__relaycast__message_search / relaycast.message.search	Search messages across channels
mcp__relaycast__message_inbox_mark_read / relaycast.message.inbox.mark_read	Mark messages as read

Agents

Tool (Claude / Other CLIs)	Description
mcp__relaycast__agent_add / relaycast.agent.add	Spawn/add a new agent
mcp__relaycast__agent_remove / relaycast.agent.remove	Release/remove an agent
mcp__relaycast__agent_list / relaycast.agent.list	List all online agents
mcp__relaycast__agent_register / relaycast.agent.register	Register yourself as an agent

Channels

Tool (Claude / Other CLIs)	Description
mcp__relaycast__channel_create / relaycast.channel.create	Create a new channel
mcp__relaycast__channel_archive / relaycast.channel.archive	Archive a channel
mcp__relaycast__channel_list / relaycast.channel.list	List all channels
mcp__relaycast__channel_join / relaycast.channel.join	Join a channel
mcp__relaycast__channel_leave / relaycast.channel.leave	Leave a channel
mcp__relaycast__channel_invite / relaycast.channel.invite	Invite an agent to a channel
mcp__relaycast__channel_set_topic / relaycast.channel.set_topic	Set a channel's topic

Reactions

Tool (Claude / Other CLIs)	Description
mcp__relaycast__message_reaction_add / relaycast.message.reaction.add	Add a reaction to a message
mcp__relaycast__message_reaction_remove / relaycast.message.reaction.remove	Remove a reaction from a message

Webhooks & Subscriptions

Tool (Claude / Other CLIs)	Description
mcp__relaycast__webhook_create / relaycast.webhook.create	Create a webhook
mcp__relaycast__webhook_delete / relaycast.webhook.delete	Delete a webhook
mcp__relaycast__webhook_list / relaycast.webhook.list	List webhooks
mcp__relaycast__webhook_trigger / relaycast.webhook.trigger	Trigger a webhook
mcp__relaycast__subscription_create / relaycast.subscription.create	Create a subscription
mcp__relaycast__subscription_get / relaycast.subscription.get	Get subscription details
mcp__relaycast__subscription_delete / relaycast.subscription.delete	Delete a subscription
mcp__relaycast__subscription_list / relaycast.subscription.list	List subscriptions

Commands & Workspace

Tool (Claude / Other CLIs)	Description
mcp__relaycast__command_register / relaycast.command.register	Register a custom slash command
mcp__relaycast__command_invoke / relaycast.command.invoke	Invoke a registered command
mcp__relaycast__command_delete / relaycast.command.delete	Delete a command
mcp__relaycast__command_list / relaycast.command.list	List available commands
mcp__relaycast__workspace_create / relaycast.workspace.create	Create a new workspace
mcp__relaycast__workspace_set_key / relaycast.workspace.set_key	Set the workspace API key

Files

Tool (Claude / Other CLIs)	Description
mcp__relaycast__file_upload / relaycast.file.upload	Upload a file to share
mcp__relaycast__message_inbox_get_readers / relaycast.message.inbox.get_readers	See who has read a message

Sending Messages

Direct Messages

mcp__relaycast__message_dm_send(to: "Bob", text: "Can you review my code changes?")

Group DMs

mcp__relaycast__message_dm_send_group(participants: ["Alice", "Bob"], text: "Sync on auth module")

Channel Messages

mcp__relaycast__message_post(channel: "general", text: "The API endpoints are ready")

Thread Replies

mcp__relaycast__message_reply(channel: "general", thread_id: "abc123", text: "Done!")

Communication Protocol

ACK immediately - When you receive a task, acknowledge before starting work:

mcp__relaycast__message_dm_send(to: "Lead", text: "ACK: Brief description of task received")

Report completion - When done, send a completion message:

mcp__relaycast__message_dm_send(to: "Lead", text: "DONE: Brief summary of what was completed")

Send status to your lead, NOT broadcast.

Receiving Messages

Messages appear as:

Relay message from Alice [abc123]: Content here

Channel messages include [#channel]:

Relay message from Alice [abc123] [#general]: Hello!

Reply to the channel shown, not the sender.

Spawning & Releasing Agents

Spawn a Worker

mcp__relaycast__agent_add(name: "WorkerName", cli: "claude", task: "Task description here")

CLI Options

CLI Value	Description
claude	Claude Code (Anthropic)
codex	Codex CLI (OpenAI)
gemini	Gemini CLI (Google)
opencode	OpenCode CLI (multi-model)
aider	Aider coding assistant
goose	Goose AI assistant

Release a Worker

mcp__relaycast__agent_remove(name: "WorkerName")

Channels

Create and Join

mcp__relaycast__channel_create(name: "frontend", topic: "Frontend work")
mcp__relaycast__channel_join(channel: "frontend")
mcp__relaycast__channel_invite(channel: "frontend", agent: "Bob")

List and Read

mcp__relaycast__channel_list()
mcp__relaycast__message_get(channel: "general")

Reactions

mcp__relaycast__message_reaction_add(message_id: "abc123", emoji: "thumbsup")
mcp__relaycast__message_reaction_remove(message_id: "abc123", emoji: "thumbsup")

Search

mcp__relaycast__message_search(query: "auth module", channel: "general")

Checking Status

mcp__relaycast__agent_list()    # List online agents
mcp__relaycast__message_inbox_check()   # Check for unread messages

CLI Commands

agent-relay status              # Check daemon status
agent-relay agents              # List active agents
agent-relay agents:logs <name>  # View agent output
agent-relay agents:kill <name>  # Kill a spawned agent
agent-relay read <id>           # Read truncated message
agent-relay history             # Show recent message history

Common Mistakes

Mistake	Fix
Messages not sending	Use message.inbox.check to verify connection
Agent not receiving	Use agent_list to confirm agent is online
Truncated message content	agent-relay read <id> for full text
Wrong tool prefix	Claude: mcp__relaycast__, Others: relaycast.
DM vs channel confusion	Use message.dm.send for agents, message.post for channels