aiti-omp-agent · Oh My Pi Backend

❝ omp's independent world: ready handshake / get_state capability surface / host tools / login / branch. ❞

The RPC spawn backend for Oh My Pi (omp.sh, a Bun-only superset fork of pi: subagents / plan mode / LSP-DAP / hindsight memory, etc.) — one independent omp --mode rpc child process per session (run by bun, stdio newline-delimited JSON protocol). Split from aiti-pi-agent to specialize in omp; the engine layer fork-rpc/ shares the same origin as pi-agent (a _shared/pi-fork-rpc deploy copy; all differences are declared via spec.commands boolean flags).

Mechanism

• CLI resolution: OMP_CLI explicit → PATH omp → fallback ~/.bun/bin/omp (systemd PATH doesn't include the bun bin); if omp isn't installed, registration proceeds as usual and createSession reports clear installation guidance
• Wire protocol: ready handshake (15s timeout fallback; dying before ready fails loud with the reason) → agent_start/turn_start/agent_end/agent_settled / model_select / queue_update (remote queue mirror) / extension_ui_request (pendingUI capped at 32; over the limit the oldest is auto-cancelled)
• Session id rebind (B4): omp has no --session-id — after ready, poll and read back the real rpcSessionId → ctx.core.rebindSessionBackend rebinds (old host degrades to skip) → bus broadcast aiti-omp-agent:rebind {from,to}; session-manager consumes it to converge placeholder rows
• Spawn env governance: governanceEnv("omp") whitelist passthrough + AITI_BRIDGE_URL always injected + extman spawn.env user list (-NAME removes an auto-injected item)

Capability Surface

steer / followUp / queueManage (list/clear/move/convert/remove/recall/requeue) / getMessages / contextUsage / setModel / setThinkingLevel / fork (branch command; omp-m<N> resolves the real entry id via sessionFile JSONL) / renameSession / compact / getCommands / listTools (get_state.dumpTools) / respondInteraction / subagents (getSubagents / subscription levels off|progress|events / getSubagentMessages). login goes through /login interception → get_login_providers → synthesized candidate select UI / direct launch → open_url frames drive the front-end login card.

P2 host tools bridge

After ready, pull the aiti-devtools bridge MCP (AITI_BRIDGE_URL) tools/list → filter by the G1 whitelist (default read-only subset of 14: aiti_inbox / page_snapshot / self_ui / user_* etc.; write-type page_exec/form_fill excluded by default) → inject into omp via set_host_tools; agent calls pass through back to the bridge via HTTP tools/call; silent degradation when the bridge is unreachable. Whitelist feature hostToolsAllow (empty = read-only subset, * = full set, comma-separated exact list).

Feature switches

spawn.env / spawn.command (docker-ized wrapper) / spawn.argsPrefix / hostToolsAllow (effective for the next session).

Relationships

aiti-pi-agent (split source, pi-only); session-manager (consumes rebind frames); aiti-devtools (host tools bridge source); aiti-custom-agent (provides the standard .launch delegation service shape; no omp-driver consumer yet).