recv: drop wait_seconds from the MCP tool, always an immediate peek

docs/conventions.md

@@ -121,10 +121,13 @@ in `hive-c0re::dashboard_events::DashboardEvent`.
 agent. Always returns a list (`Messages { messages }`) — empty when
 nothing's pending, single-pop when `max = None` (default 1, the
 single-message behaviour), batched up to `max` when caller asks for
-more (server-side cap is 5; values above clamp silently).
-`wait_seconds` long-polls for the first message; once one arrives —
-or one is already pending — the call drains up to `max` in total
-before returning, so a single `Recv` call coalesces a burst.
+more (server-side cap is 5; values above clamp silently). The wire
+request still carries an optional `wait_seconds` (long-poll the first
+message, once one arrives — or one is already pending — the call
+drains up to `max` in total): the harness's own turn-driving loop
+uses it internally (`hive-agent`'s `recv_next`, 180s). The
+agent-facing MCP `recv` tool no longer exposes this parameter at all
+(#2814) — it always passes `wait_seconds: None`, an immediate peek.
 
 Per-row bookkeeping inside the broker:
 

docs/turn-loop/mcp.md

@@ -23,7 +23,7 @@ preset (`AGENT_DEFAULT`) includes `messaging`, `meta`, `inbox`, and
 ## Core tools (always available)
 
 **Messaging** (`messaging` group): `send(to, body, in_reply_to?)`,
-`recv(wait_seconds?, max?)`, `ask(question, options?, multi?,
+`recv(max?)`, `ask(question, options?, multi?,
 ttl_seconds?, to?)`, `answer(id, answer)`, `ack_until(up_to)`.
 
 - `send` — message a peer (logical name) or the operator
@@ -36,11 +36,10 @@ ttl_seconds?, to?)`, `answer(id, answer)`, `ack_until(up_to)`.
   `[ "operator" ]` to restrict a sub-agent to operator messages only
   (the topology parent is always reachable regardless of this list —
   that carve-out is structural, keyed on parent relationship, not name).
-- `recv` — drain inbox. Without `wait_seconds` (or `0`) returns
-  immediately. Positive value parks the turn up to that many seconds
-  (cap 180) — incoming messages wake instantly. `max` (default 1, cap
-  5) drains up to N rows; `wait_seconds` applies to the first, then
-  drains up to `max` total. Each returned row is prefixed with
+- `recv` — drain inbox. Always an immediate peek, never blocks (#2814
+  — dropped the `wait_seconds` long-poll param entirely; nobody had a
+  use case for it that wasn't already better served by ending the
+  turn). `max` (default 1, cap 5) drains up to N rows. Each returned row is prefixed with
   `[msg #<id>]` (broker row id; note the highest id seen, then pass
   it to `ack_until` to bulk-triage the batch). **Graceful shutdown**: when the harness
   receives a stop signal, the inbox becomes fenced and `recv` returns an