fix(mcp): report real tier/ELO/G on idempotent arena_submit re-submit

[colinisme]

Problem

arena_submit reports a misleading Tier: Bronze, ELO 0, G at submit: 0 when an agent that is already in the matchmaking pool re-submits — even though the ghost is correctly sitting in its real tier (e.g. Gold) and matchmaking pairs it there.

Reproduced live on mainnet while running Arena battles for three agents: Colin111 (#32) was already pooled from a prior session, so its re-submit printed Bronze / 0 / 0 — yet it was matched in Gold and won. The on-chain submission was always correct; only the MCP's return message was wrong.

Root cause

ArenaEngine.submit() is intentionally idempotent:

// ArenaEngine.sol:408
if (!isSubmitted[agentId]) {
    ...
    emit GhostSubmitted(agentId, t, g.elo, gNow);
}

A re-submit of an already-pooled ghost is a no-op that emits no GhostSubmitted event. arenaSubmit() parsed only that event, so when it was absent the function fell through to its tier = 0, elo = 0, gAtSubmit = 0 defaults → Bronze / 0 / 0. (settleMatch clears isSubmitted, which is why agents that had just fought re-submitted with correct values and never showed the bug.)

Fix

When no GhostSubmitted event is found, fall back to live on-chain reads instead of the zero defaults:

• arena.tierStates([agentId]) → real tier + G balance
• arena.getGhost(agentId) → real ELO

The tool message now leads with "Already in the pool" for the no-op case so it's honest about what happened, and adds an alreadyPooled flag to the return shape.

Verification (live, Gravity mainnet)

Scenario	Before	After
Fresh submit (event emitted)	Ghost submitted! Tier: Gold, ELO 1017, G 2175	unchanged ✅
Re-submit, already pooled (no event)	Ghost submitted! Tier: Bronze, ELO 0, G 0 ❌	Already in the pool Tier: Gold, ELO 1017, G 2175 ✅

tier_info confirms ground truth = Gold / 2175. tsc --noEmit passes; the tracked bin/gravity-town-mcp.mjs bundle was rebuilt from the patched source.

🤖 Generated with Claude Code

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Project	Deployment	Actions	Updated (UTC)
gravity-town	Ready	Preview, Comment	Jun 5, 2026 4:57am