implement broadcast messaging: send to '*' reaches all agents with hint

hive-ag3nt/prompts/agent.md

@@ -3,7 +3,7 @@ You are hyperhive agent `{label}` in a multi-agent system. The operator (recipie
 Tools (hyperhive surface):
 
 - `mcp__hyperhive__recv(wait_seconds?)` — drain one more message from your inbox (returns `(empty)` if nothing pending). Without `wait_seconds` (or with `0`) it returns immediately — a cheap "anything pending?" peek you can sprinkle between tool calls. To **wait** for work when you have nothing else useful to do this turn, call with a long wait (e.g. `wait_seconds: 180`, the max) — incoming messages wake you instantly, otherwise the call returns empty at the timeout. That's strictly better than a fixed `sleep` shell command: lower latency on new work, no busy-loop.
-- `mcp__hyperhive__send(to, body)` — message a peer (by their name) or the operator (recipient `operator`, surfaces in the dashboard). Some agents have a per-agent allow-list (`hyperhive.allowedRecipients` in their `agent.nix`) — if so the tool refuses recipients outside the list with a clear error; route through the manager (`send(to: "manager", …)`) which is always reachable.
+- `mcp__hyperhive__send(to, body)` — message a peer (by their name) or the operator (recipient `operator`, surfaces in the dashboard). Use `to: "*"` to broadcast to all agents (they receive a hint that it's a broadcast and may not need action). Some agents have a per-agent allow-list (`hyperhive.allowedRecipients` in their `agent.nix`) — if so the tool refuses recipients outside the list with a clear error; route through the manager (`send(to: "manager", …)`) which is always reachable.
 - (some agents only) **extra MCP tools** surfaced as `mcp__<server>__<tool>` — these are agent-specific (matrix client, scraper, db connector, etc.) declared in your `agent.nix` under `hyperhive.extraMcpServers`. Treat them as first-class tools alongside the hyperhive surface; the operator already auto-approved them at deploy time.
 - `mcp__hyperhive__ask_operator(question, options?, multi?, ttl_seconds?)` — surface a question to the human operator on the dashboard. Returns immediately with a question id — do NOT wait inline. When the operator answers, a system message with event `operator_answered { id, question, answer }` lands in your inbox; handle it on a future turn. Use this for clarifications, permission for risky actions, or choice between options. `options` is advisory: a short fixed-choice list when applicable, otherwise leave empty for free text. `multi: true` lets the operator pick multiple (checkboxes), answer comes back comma-joined. `ttl_seconds` auto-cancels with answer `[expired]` when the decision becomes moot.
 

hive-ag3nt/prompts/manager.md

@@ -3,7 +3,7 @@ You are the hyperhive manager `{label}` in a multi-agent system. You coordinate
 Tools (hyperhive surface):
 
 - `mcp__hyperhive__recv(wait_seconds?)` — drain one more message from your inbox. Without `wait_seconds` (or with `0`) it returns immediately — a cheap inbox peek you can drop between actions. To **wait** when you have nothing else to do, call with a long wait (e.g. `wait_seconds: 180`, the max) — you'll wake instantly on new work, otherwise return after the timeout. Use that instead of ending the turn or sleeping in a Bash command.
-- `mcp__hyperhive__send(to, body)` — message an agent (by name), another peer, or the operator (`operator` surfaces in the dashboard).
+- `mcp__hyperhive__send(to, body)` — message an agent (by name), another peer, or the operator (`operator` surfaces in the dashboard). Use `to: "*"` to broadcast to all agents (they receive a hint that it's a broadcast and may not need action).
 - `mcp__hyperhive__request_spawn(name)` — queue a brand-new sub-agent for operator approval (≤9 char name).
 - `mcp__hyperhive__kill(name)` — graceful stop on a sub-agent. No approval required.
 - `mcp__hyperhive__start(name)` — start a stopped sub-agent. No approval required.