Two coding agents lived in an MMO for a week: give them sight, not a shell

Unusual-Spot-5846 · reddit · 2026-11-03

For one week Claude Code and Codex CLI each controlled a party member on an offline WoW 3.3.5a research server, taking natural-language orders in party chat; they wrote 8.4k lines of C++, 5.4k lines of Python and 57 unit tests making it work.
Design principle "sight without authority": bounded read-only world snapshots plus 29 typed, server-validated actions—no shell, no SQL, no credentials; agents themselves refused unrestricted command execution.
Key lessons: "accepted" isn't "done" (confirm by observation); silent refusal is the most damaging interface failure (one dropped line made stairs impassable); schemas should follow natural speech (only location required); every truncated context needs a visible flag (40-object snapshot hid a nearby NPC; E2BIG prompt overflow killed 18 calls in 35 minutes).

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