Quick summary: In Oh-my-pi (OMP), a role is a routing alias, not an agent. The main session, a mode, or a subagent asks for
@role, andmodelRolesresolves that alias to a model plus a reasoning effort. Fallback is a separate layer inretry.fallbackChains: OMP only tries it, in order, when the running model fails, and it never load-balances. Assign models by call frequency and decision weight, then read back what is running in/model,/agents, and the status line.
I wrote this after paying for a strong model on chores that ran hundreds of times a day, and after believing my config was right while a role had quietly dropped back to auto-selection. The routing table here is my own setup, not an OMP default.
Versions I checked: the mechanics were checked against the docs and source of OMP 18.4.0 (the version installed on my machine) on 2026-10-03, plus the changelog up to 18.4.12. The config table is a snapshot from 2026-08-26. OMP changes its role list fairly often, so open /changelog before you copy anything.
I split models by workload, not by intelligence
For each role I ask two questions: how often does this role get called, and what does a wrong answer cost?
Total resource ≈ cost per call × call frequency × context volume × reasoning effortA role that writes session titles runs after every new session, so a cheap model is enough. A planning role runs a few times, but one wrong plan sends the whole session off course, so a strong model is worth paying for.
That gives me three groups. plan and slow are called rarely but set direction, so they get a strong model with high reasoning. tiny, memory, commit, smol, and background utilities run often or do narrow work, so they need to be cheap, fast, and stable. default sits in the middle: used constantly, strong enough, not necessarily maximal. Reasoning effort is its own resource too. Do not put every role on max; pick effort by decision weight and call frequency.
advisor is a special case. Its review is valuable, but it can run after every turn, so measure tokens and cost before raising its model or effort.
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- Version
- v1.0.0
- Updated
- 26/08/2026
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- Subscriber-only; redistribution prohibited
- Slug
- omp-model-routing-guide
