| 1 | //! The single shared turn-route planner (#1004). |
| 2 | //! |
| 3 | //! One function decides which provider, model, route identity, client, limits, |
| 4 | //! compaction policy, and reasoning tier a turn will use. |
| 5 | //! `spawned_dispatch_inner` calls it to *send* a turn; `/preview-request` |
| 6 | //! calls it with a hypothetical prompt to *describe* one. Because there is a |
| 7 | //! single implementation, a preview cannot report a route different from the |
| 8 | //! one dispatch would pick for the same prompt — which is the whole point of |
| 9 | //! previewing a route before spending anything on it. |
| 10 | //! |
| 11 | //! It lives outside the TUI module so the engine-side preview tests can drive |
| 12 | //! the same planner the UI drives, provider-free. |
| 13 | //! |
| 14 | //! The planner mutates no engine or session state. Its one outbound call is |
| 15 | //! the auto-router classifier, which only runs when auto model routing is on. |
| 16 | //! Production may use the deterministic response cache for that call; |
| 17 | //! `/preview-request` explicitly bypasses it so inspection does not perturb |
| 18 | //! later routing. |
| 19 | |
| 20 | use crate::compaction::CompactionConfig; |
| 21 | use crate::config::{ApiProvider, Config, ProviderIdentity}; |
| 22 | use crate::route_runtime::{ |
| 23 | ResolvedRuntimeRoute, resolve_runtime_route, resolve_runtime_route_for_identity, |
| 24 | }; |
| 25 | use crate::tui::app::{AppMode, ReasoningEffort}; |
| 26 | |
| 27 | /// Everything the shared turn-route planner needs. |
| 28 | /// |
| 29 | /// Borrowed rather than owned so the dispatch path can pass its already |
| 30 | /// captured `UserDispatchPrepare` fields and `/preview-request` can pass a |
| 31 | /// hypothetical prompt, without either one duplicating the other's logic. |
| 32 | pub(crate) struct TurnRoutePlanRequest<'a> { |
| 33 | pub(crate) route_config: &'a Config, |
| 34 | pub(crate) app_route_identity: &'a ProviderIdentity, |
| 35 | pub(crate) api_provider: ApiProvider, |
| 36 | pub(crate) app_model: &'a str, |
| 37 | pub(crate) auto_model: bool, |
| 38 | pub(crate) reasoning_effort: ReasoningEffort, |
| 39 | pub(crate) mode: AppMode, |
| 40 | /// Model-facing content of the next user message (file mentions and skill |
| 41 | /// wrapping already resolved). This is what the auto router classifies. |
| 42 | pub(crate) content: &'a str, |
| 43 | /// The user's display text, used by the heuristic and auto-reasoning |
| 44 | /// fallbacks exactly as production does. |
| 45 | pub(crate) display_text: &'a str, |
| 46 | pub(crate) auto_router_context: &'a str, |
| 47 | pub(crate) should_auto_resolve: bool, |
| 48 | /// Production dispatch may use the deterministic response cache for the |
| 49 | /// auxiliary Auto classifier. Read-only previews must set this to false. |
| 50 | pub(crate) allow_auto_router_response_cache: bool, |
| 51 | pub(crate) preflight_required: bool, |
| 52 | pub(crate) auto_compact_user_configured: bool, |
| 53 | pub(crate) auto_compact: bool, |
| 54 | pub(crate) auto_compact_threshold_percent: f64, |
| 55 | } |
| 56 | |
| 57 | /// The exact route, limits, compaction policy, and reasoning normalization one |
| 58 | /// turn would use. |
| 59 | pub(crate) struct PlannedTurnRoute { |
| 60 | pub(crate) route: ResolvedRuntimeRoute, |
| 61 | pub(crate) compaction: CompactionConfig, |
| 62 | pub(crate) effective_provider: ApiProvider, |
| 63 | pub(crate) effective_model: String, |
| 64 | pub(crate) effective_provider_identity: String, |
| 65 | pub(crate) effective_provider_label: String, |
| 66 | pub(crate) selected_reasoning_effort: Option<ReasoningEffort>, |
| 67 | /// Normalized api value for the resolved route — the string that reaches |
| 68 | /// the wire. |
| 69 | pub(crate) effective_reasoning_effort: Option<String>, |
| 70 | pub(crate) auto_controls_reasoning: bool, |
| 71 | pub(crate) auto_selection: Option<crate::model_routing::AutoRouteSelection>, |
| 72 | /// Why this concrete route was selected. This is captured by the planner, |
| 73 | /// not inferred later from the resulting provider/model pair. |
| 74 | pub(crate) routing_source: TurnRoutingSource, |
| 75 | } |
| 76 | |
| 77 | /// Durable provenance for the route selected for one turn. |
| 78 | #[derive(Debug, Clone, Copy, PartialEq, Eq)] |
| 79 | pub(crate) enum TurnRoutingSource { |
| 80 | /// The active fixed route was used unchanged. This intentionally does not |
| 81 | /// guess whether an earlier UI action or persisted config installed it. |
| 82 | ActiveFixedRoute, |
| 83 | /// Auto model routing used its provider-backed classifier. |
| 84 | AutoProviderClassifier, |
| 85 | /// Auto model routing used the local deterministic fallback heuristic. |
| 86 | AutoLocalHeuristic, |
| 87 | } |
| 88 | |
| 89 | impl TurnRoutingSource { |
| 90 | pub(crate) const fn label(self) -> &'static str { |
| 91 | match self { |
| 92 | Self::ActiveFixedRoute => "active-fixed-route", |
| 93 | Self::AutoProviderClassifier => "auto-provider-classifier", |
| 94 | Self::AutoLocalHeuristic => "auto-local-heuristic", |
| 95 | } |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | fn reasoning_effort_for_route_selection( |
| 100 | auto_model: bool, |
| 101 | provider: ApiProvider, |
| 102 | effort: ReasoningEffort, |
| 103 | ) -> &'static str { |
| 104 | if auto_model { |
| 105 | effort.as_setting() |
| 106 | } else { |
| 107 | effort.as_setting_for_provider(provider) |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | /// Resolve the route for one turn. |
| 112 | /// |
| 113 | /// This is *the* route planner (#1004). `spawned_dispatch_inner` calls it to |
| 114 | /// send a turn; `/preview-request` calls it with a hypothetical prompt to |
| 115 | /// describe one. Because there is a single implementation, a preview cannot |
| 116 | /// report a provider, model, route identity, client, reasoning tier, limit, |
| 117 | /// tool budget, billing basis, or endpoint different from the one dispatch |
| 118 | /// would pick for the same prompt. |
| 119 | /// |
| 120 | /// It mutates no engine or session state: it reads config, resolves a route, |
| 121 | /// and returns a value. Its one outbound call is the auto-router classifier, |
| 122 | /// which is the same auxiliary call a real turn makes and only runs when auto |
| 123 | /// model routing is on. The caller chooses whether that auxiliary call may |
| 124 | /// touch the process-global deterministic response cache. |
| 125 | pub(crate) async fn plan_turn_route( |
| 126 | request: TurnRoutePlanRequest<'_>, |
| 127 | ) -> Result<PlannedTurnRoute, String> { |
| 128 | let auto_selection = if request.should_auto_resolve { |
| 129 | Some( |
| 130 | crate::model_routing::resolve_auto_route_with_inventory_for_session_and_cache_policy( |
| 131 | request.route_config, |
| 132 | request.content, |
| 133 | request.auto_router_context, |
| 134 | request.mode.as_setting(), |
| 135 | if request.auto_model { "auto" } else { "fixed" }, |
| 136 | reasoning_effort_for_route_selection( |
| 137 | request.auto_model, |
| 138 | request.api_provider, |
| 139 | request.reasoning_effort, |
| 140 | ), |
| 141 | request.allow_auto_router_response_cache, |
| 142 | ) |
| 143 | .await |
| 144 | .map_err(|err| err.to_string())?, |
| 145 | ) |
| 146 | } else { |
| 147 | None |
| 148 | }; |
| 149 | |
| 150 | let effective_provider = auto_selection |
| 151 | .as_ref() |
| 152 | .map(|selection| selection.provider) |
| 153 | .unwrap_or(request.api_provider); |
| 154 | |
| 155 | let effective_model = if request.auto_model { |
| 156 | auto_selection |
| 157 | .as_ref() |
| 158 | .map(|selection| selection.model.clone()) |
| 159 | .unwrap_or_else(|| { |
| 160 | crate::model_routing::auto_model_heuristic(request.display_text, request.app_model) |
| 161 | }) |
| 162 | } else { |
| 163 | request.app_model.to_string() |
| 164 | }; |
| 165 | |
| 166 | let turn_route = if effective_provider == request.app_route_identity.provider { |
| 167 | resolve_runtime_route_for_identity( |
| 168 | request.route_config, |
| 169 | request.app_route_identity, |
| 170 | Some(&effective_model), |
| 171 | ) |
| 172 | } else { |
| 173 | resolve_runtime_route( |
| 174 | request.route_config, |
| 175 | effective_provider, |
| 176 | Some(&effective_model), |
| 177 | ) |
| 178 | }; |
| 179 | |
| 180 | let turn_route = turn_route.map_err(|err| err.to_string())?; |
| 181 | let turn_route = if request.preflight_required { |
| 182 | turn_route.preflight()? |
| 183 | } else { |
| 184 | turn_route |
| 185 | }; |
| 186 | |
| 187 | let turn_route_limits = crate::route_budget::known_route_limits(turn_route.candidate.limits()); |
| 188 | let effective_provider_identity = turn_route.identity.key.clone(); |
| 189 | let effective_provider_label = if effective_provider == ApiProvider::Custom { |
| 190 | effective_provider_identity.clone() |
| 191 | } else { |
| 192 | effective_provider.display_name().to_string() |
| 193 | }; |
| 194 | |
| 195 | let turn_compaction = CompactionConfig { |
| 196 | enabled: if request.auto_compact_user_configured { |
| 197 | request.auto_compact |
| 198 | } else { |
| 199 | crate::route_budget::auto_compact_default_for_route( |
| 200 | turn_route.identity.provider, |
| 201 | &turn_route.model, |
| 202 | turn_route_limits, |
| 203 | ) |
| 204 | }, |
| 205 | token_threshold: crate::route_budget::compaction_threshold_for_route_at_percent( |
| 206 | turn_route.identity.provider, |
| 207 | &turn_route.model, |
| 208 | turn_route_limits, |
| 209 | request.auto_compact_threshold_percent, |
| 210 | ), |
| 211 | model: turn_route.model.clone(), |
| 212 | effective_context_window: Some(crate::route_budget::route_context_window_tokens( |
| 213 | turn_route.identity.provider, |
| 214 | &turn_route.model, |
| 215 | turn_route_limits, |
| 216 | )), |
| 217 | ..Default::default() |
| 218 | }; |
| 219 | |
| 220 | // Model selection and reasoning selection are independent. A fixed |
| 221 | // reasoning preference survives auto model routing and is normalized |
| 222 | // against the concrete route below; only an explicit `auto` delegates the |
| 223 | // tier to the classifier/heuristic. |
| 224 | let auto_controls_reasoning = request.reasoning_effort == ReasoningEffort::Auto; |
| 225 | let selected_reasoning_effort = if auto_controls_reasoning { |
| 226 | Some( |
| 227 | auto_selection |
| 228 | .as_ref() |
| 229 | .and_then(|selection| selection.reasoning_effort) |
| 230 | .unwrap_or_else(|| crate::auto_reasoning::select(false, request.display_text)), |
| 231 | ) |
| 232 | } else { |
| 233 | None |
| 234 | }; |
| 235 | |
| 236 | let effective_reasoning_effort = selected_reasoning_effort |
| 237 | .unwrap_or(request.reasoning_effort) |
| 238 | .api_value_for_route( |
| 239 | effective_provider, |
| 240 | &turn_route.candidate.endpoint().base_url, |
| 241 | &turn_route.model, |
| 242 | ) |
| 243 | .map(str::to_string); |
| 244 | |
| 245 | let routing_source = if !request.auto_model { |
| 246 | TurnRoutingSource::ActiveFixedRoute |
| 247 | } else if auto_selection.is_some() { |
| 248 | TurnRoutingSource::AutoProviderClassifier |
| 249 | } else { |
| 250 | TurnRoutingSource::AutoLocalHeuristic |
| 251 | }; |
| 252 | |
| 253 | Ok(PlannedTurnRoute { |
| 254 | route: turn_route, |
| 255 | compaction: turn_compaction, |
| 256 | effective_provider, |
| 257 | effective_model, |
| 258 | effective_provider_identity, |
| 259 | effective_provider_label, |
| 260 | selected_reasoning_effort, |
| 261 | effective_reasoning_effort, |
| 262 | auto_controls_reasoning, |
| 263 | auto_selection, |
| 264 | routing_source, |
| 265 | }) |
| 266 | } |
| 267 | |
| 268 | #[cfg(test)] |
| 269 | mod tests { |
| 270 | use super::*; |
| 271 | use crate::config::DEFAULT_TEXT_MODEL; |
| 272 | |
| 273 | fn deepseek_identity() -> ProviderIdentity { |
| 274 | ProviderIdentity { |
| 275 | provider: ApiProvider::Deepseek, |
| 276 | key: ApiProvider::Deepseek.as_str().to_string(), |
| 277 | exact_id: None, |
| 278 | } |
| 279 | } |
| 280 | |
| 281 | #[test] |
| 282 | fn auto_model_route_selection_keeps_raw_reasoning_preference() { |
| 283 | assert_eq!( |
| 284 | reasoning_effort_for_route_selection( |
| 285 | true, |
| 286 | ApiProvider::OpenaiCodex, |
| 287 | ReasoningEffort::Off, |
| 288 | ), |
| 289 | "off" |
| 290 | ); |
| 291 | assert_eq!( |
| 292 | reasoning_effort_for_route_selection( |
| 293 | false, |
| 294 | ApiProvider::OpenaiCodex, |
| 295 | ReasoningEffort::Off, |
| 296 | ), |
| 297 | "low" |
| 298 | ); |
| 299 | } |
| 300 | |
| 301 | #[tokio::test] |
| 302 | async fn auto_model_route_respects_fixed_reasoning_preference() { |
| 303 | let config = Config::default(); |
| 304 | let identity = deepseek_identity(); |
| 305 | |
| 306 | let planned = plan_turn_route(TurnRoutePlanRequest { |
| 307 | route_config: &config, |
| 308 | app_route_identity: &identity, |
| 309 | api_provider: ApiProvider::Deepseek, |
| 310 | app_model: DEFAULT_TEXT_MODEL, |
| 311 | auto_model: true, |
| 312 | reasoning_effort: ReasoningEffort::Low, |
| 313 | mode: AppMode::Agent, |
| 314 | content: "explain this function", |
| 315 | display_text: "explain this function", |
| 316 | auto_router_context: "", |
| 317 | should_auto_resolve: false, |
| 318 | allow_auto_router_response_cache: false, |
| 319 | preflight_required: false, |
| 320 | auto_compact_user_configured: false, |
| 321 | auto_compact: true, |
| 322 | auto_compact_threshold_percent: 80.0, |
| 323 | }) |
| 324 | .await |
| 325 | .expect("plan auto-model turn"); |
| 326 | |
| 327 | assert_eq!( |
| 328 | planned.routing_source, |
| 329 | TurnRoutingSource::AutoLocalHeuristic |
| 330 | ); |
| 331 | assert!(!planned.auto_controls_reasoning); |
| 332 | assert_eq!(planned.selected_reasoning_effort, None); |
| 333 | // First-party DeepSeek routes carry low as the real wire tier |
| 334 | // (`reasoning_effort` low/high/max are documented); the App keeps the |
| 335 | // unresolved preference as Low either way. |
| 336 | assert_eq!(planned.effective_reasoning_effort.as_deref(), Some("low")); |
| 337 | } |
| 338 | } |
| 339 |