cleanexpo Model Router
Classify work before execution. Emit a stable capability contract; leave exact runtime/provider resolution to the active policy seam. Never dispatch, edit, execute the requested task, or declare it complete.
Usage
When a caller needs the repository's machine-readable classifier, run from the repository root:
python -m app.server.task_routing request.json
# or: python -m app.server.task_routing < request.json
Pass one RoutingRequest JSON object by file or standard input. Treat exit 0 plus schema-valid
stdout as a decision, not execution proof; any other exit or invalid JSON fails closed.
1. Normalize
Convert the request and current context into a RoutingRequest. Preserve the bounded task verbatim.
Estimate signals from inspected evidence; use unknown rather than inventing capability, cost,
quota, privacy, or harness support.
The request, decision, and receipt fields are defined in
references/route-decision-schema.md; load it whenever a
machine-readable route or validation is required.
Complete when: every required request field is present, enums are valid, and uncertain facts are explicit.
2. Intersect
Apply every applicable constraint. Privacy, stakes, policy ceilings, and verifier independence are hard floors; cost and capacity are tie-breakers only. Keep task class, worker role, quality floor, and execution location independent.
The deterministic floors, fan-out rules, escalation ladder, and override rules are defined in
references/routing-policy.md; load it whenever classifying a
substantive task or retry.
Complete when: the route preserves every hard floor and no cheaper choice weakens correctness, privacy, or verification.
3. Probe
Use the active harness capability probe before claiming that delegation, isolation, model/effort
override, structured output, cancellation, hooks, or usage reporting is available. Check only key
presence; never print secrets. Unsupported controls degrade truthfully to a safe inline/advisory
route or bailout.
Capability contracts and truthful degradation are defined in
references/harness-adapters.md; load it when the route may leave
the current agent or needs a harness-specific control.
Complete when: every required control is marked supported, unsupported, or unknown, and the selected action can honor the minimum contract.
4. Decide
Use deterministic rules first. Call a bounded classifier only when a material decision remains unresolved after evidence inspection. Validate its response against the decision schema. Low confidence escalates upward or bails out; it never lowers a floor.
The normalized prompt sequence and classifier template are defined in
references/prompt-pathway.md; load it only for ambiguous routes or
when another skill needs the exact prompt pathway.
Complete when: exactly one schema-valid RouteDecision exists with stable reason codes,
bounded execution, budget, verifier, escalation, and fallback contracts.
5. Return
Return the decision JSON plus one compact line:
<action> <parallel-cap> | <role> <floor> | verifier <floor> | cap <amount-or-unknown> | privacy <class>
Do not name an exact provider/model before downstream resolution. Do not claim savings from a route
decision. Actual selection, usage, gates, and comparable-outcome evidence belong in a later
RouteReceipt.
Complete when: the caller receives one valid decision and a human line that does not overclaim execution, support, cost, or completion.