645 lines
34 KiB
Markdown
645 lines
34 KiB
Markdown
---
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title: "OmniRoute Auto-Combo Engine"
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version: 3.8.40
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lastUpdated: 2026-06-28
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---
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# OmniRoute Auto-Combo Engine
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> **For Users**: Looking for a quick start? See the [Auto-Combo User Guide](../getting-started/AUTO-COMBO-GUIDE.md) for simple explanations and examples.
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> Self-managing model chains with adaptive scoring + zero-config auto-routing
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## Zero-Config Auto-Routing (`auto/` prefix)
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> **NEW:** No combo creation required. Use `auto/` prefix directly in any client.
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### Quick Examples
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| Model ID | Variant | Behavior |
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| -------------- | ------- | ------------------------------------------------------------------------ |
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| `auto` | default | All connected providers, LKGP strategy, balanced weights |
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| `auto/coding` | coding | Quality-first weights, suitable for code generation |
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| `auto/fast` | fast | Low-latency weighted selection |
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| `auto/cheap` | cheap | Cost-optimized routing (lowest cost first) |
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| `auto/offline` | offline | Favors providers with highest quota availability |
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| `auto/smart` | smart | Quality-first + higher exploration rate (10%) for better model discovery |
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| `auto/lkgp` | lkgp | Explicit LKGP (same as default `auto`) |
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### Category × Tier Composition (`auto/<category>:<tier>`)
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OpenRouter-style suffixes separate **what kind of route** (category) from **how to optimize it** (tier), so you can compose them freely (#4235 Phase B, `open-sse/services/autoCombo/suffixComposition.ts`):
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- **Categories** (filter the candidate pool by capability): `coding` · `reasoning` · `vision` · `chat` · `multimodal`. `vision`/`multimodal` keep vision-capable models; `reasoning` keeps reasoning/thinking models.
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- **Tiers** (pick the scoring weights / pool filter): `fast` (ship-fast) · `cheap` (alias `floor`, cost-saver) · `reliable` (circuit-breaker health + latency stability) · `free` / `pro` (filter the pool by model tier via `classifyTier` — free-tier vs. premium).
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| Example | Resolves to |
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| ---------------------- | ------------------------------------------------------- |
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| `auto/coding:fast` | coding pool, low-latency weights |
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| `auto/coding:cheap` | coding pool, cost-optimized (alias `auto/coding:floor`) |
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| `auto/reasoning:pro` | reasoning/thinking models only, premium tier |
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| `auto/vision` | vision-capable models (no tier → balanced weights) |
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| `auto/multimodal:free` | multimodal-capable models, free tier only |
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Any valid `auto/<category>[:<tier>]` resolves on demand; a curated subset is advertised in `/v1/models` and the dashboard (`AUTO_SUFFIX_VARIANTS` in `open-sse/services/autoCombo/builtinCatalog.ts`). Filtering is **fail-open** — if a constraint matches no connected models, the full pool is used so routing never breaks. The core scorer (`combo.ts`) is unchanged; the category/tier filter is applied in `buildAutoCandidates`.
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> **Live model intelligence:** auto-routing fitness is informed by live **Arena ELO** rankings + **models.dev** tier data when the `ARENA_ELO_SYNC_ENABLED` flag is on (falls back to the static fitness map otherwise).
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**How to use:**
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```bash
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# Any IDE or CLI tool that supports OpenAI format
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Base URL: http://localhost:20128/v1
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API Key: <your-endpoint-key>
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# In your code/config, set model to:
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model: "auto" # balanced default
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model: "auto/coding" # best for coding tasks
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model: "auto/fast" # fastest available
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model: "auto/cheap" # cheapest per token
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```
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**What happens:**
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1. OmniRoute detects `auto/` prefix in `src/sse/handlers/chat.ts`
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2. Queries all **active provider connections** from the database
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3. Filters to those with valid credentials (API key or OAuth token)
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4. Determines the model per connection (`connection.defaultModel` or provider's first model)
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5. Builds a **virtual combo** in-memory (not stored in DB)
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6. Routes using the selected variant's weight profile + LKGP strategy
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**Key properties:**
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- ✅ **Always-on:** No toggle, no combo creation, no configuration needed
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- ✅ **Dynamic:** Reflects current connected providers automatically
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- ✅ **Session stickiness:** LKGP ensures last successful provider is prioritized
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- ✅ **Multi-account aware:** Each provider connection becomes a separate candidate
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- ✅ **No DB writes:** Virtual combo exists only for the request, zero persistence overhead
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**Behind the scenes:**
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```txt
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Request: { model: "auto/coding" }
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↓
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src/sse/handlers/chat.ts detects prefix
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↓
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createVirtualAutoCombo('coding') → candidatePool from active connections
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↓
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handleComboChat (same engine as persisted combos)
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↓
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Auto-scoring selects best provider/model per request
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```
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**Implementation files:**
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| File | Purpose |
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| --------------------------------------------------------- | ----------------------------------------- |
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| `open-sse/services/autoCombo/autoPrefix.ts` | Prefix parser (`parseAutoPrefix`) |
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| `open-sse/services/autoCombo/virtualFactory.ts` | Creates virtual `AutoComboConfig` objects |
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| `open-sse/services/autoCombo/providerRegistryAccessor.ts` | Test hook for mocking provider registry |
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| `src/sse/handlers/chat.ts` | Integration: auto prefix short-circuit |
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| `src/shared/constants/providers.ts` | `SYSTEM_PROVIDERS.auto` system entry |
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## How It Works (Persisted Auto-Combos)
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The Auto-Combo Engine dynamically selects the best provider/model for each request using a **12-factor scoring function** (defined in `open-sse/services/autoCombo/scoring.ts` → `DEFAULT_WEIGHTS`). All weights sum to **1.0**.
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> Source: [diagrams/auto-combo-12factor.mmd](../diagrams/auto-combo-12factor.mmd) (regenerate via `npm run docs:render-diagrams`).
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| Factor | Default Weight | Description |
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| :-------------------- | :------------- | :------------------------------------------------------------------------------------------------- |
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| `health` | 0.20 | Health score from circuit breaker (CLOSED=1.0, HALF_OPEN=0.5, OPEN=0.0) |
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| `quota` | 0.15 | Remaining quota / rate-limit headroom [0..1] |
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| `costInv` | 0.15 | Inverse **blended** cost (60% input + 40% output token price, normalized) — cheaper = higher score |
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| `latencyInv` | 0.12 | Inverse p95 latency normalized to pool — faster = higher score |
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| `taskFit` | 0.08 | Task-type fitness (coding, review, planning, analysis, debugging, docs) |
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| `stability` | 0.05 | Variance-based stability (low latency stdDev / error rate) |
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| `tierPriority` | 0.05 | Account-tier priority — Ultra=1.0, Pro=0.67, Standard=0.33, Free=0.0 |
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| `tierAffinity` | 0.05 | Affinity between the candidate's tier and the manifest-recommended tier |
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| `specificityMatch` | 0.05 | Match between request specificity (manifest hint) and model tier |
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| `contextAffinity` | 0.05 | Affinity between the request's context-window need and the model's context window |
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| `connectionDensity` | 0.05 | Spreads load across connections of the same provider (anti-concentration) |
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| `resetWindowAffinity` | 0.00 | Bias toward connections whose quota reset window is favorable (disabled by default) |
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**Sum:** `0.20 + 0.15 + 0.15 + 0.12 + 0.08 + 0.05 + 0.05 + 0.05 + 0.05 + 0.05 + 0.05 + 0.00 = 1.0` (validated by `validateWeights()`).
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## Mode Packs
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Four pre-defined weight profiles in `open-sse/services/autoCombo/modePacks.ts`. Each pack overrides the default weights to bias selection toward a specific goal. Below are the **full weight tables per pack** (each row sums to 1.0).
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| Factor | ship-fast | cost-saver | quality-first | offline-friendly |
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| :----------- | :-------- | :--------- | :------------ | :--------------- |
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| quota | 0.14 | 0.14 | 0.10 | **0.37** |
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| health | 0.28 | 0.19 | 0.18 | 0.28 |
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| costInv | 0.05 | **0.37** | 0.05 | 0.10 |
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| latencyInv | **0.32** | 0.05 | 0.05 | 0.05 |
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| taskFit | 0.10 | 0.10 | **0.37** | 0.00 |
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| stability | 0.00 | 0.05 | 0.15 | 0.10 |
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| tierPriority | 0.05 | 0.05 | 0.05 | 0.05 |
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Notes:
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- `tierAffinity` and `specificityMatch` are not set in mode packs — `calculateScore()` treats them as `?? 0` when absent.
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- Each pack's emphasis at a glance:
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- **ship-fast** → latencyInv 0.32 + health 0.28 (low-latency, healthy connections)
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- **cost-saver** → costInv 0.37 (cheapest tokens win)
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- **quality-first** → taskFit 0.37 + stability 0.15 (best model for the task, consistent)
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- **offline-friendly** → quota 0.37 + health 0.28 (max headroom regardless of speed/cost)
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### Per-Request Controls (headers) — #6023 / #6024 / #6025
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An `auto` combo can be steered **per request** via two headers, without mutating the
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combo's stored config. These apply only to the `auto` strategy and only for the request
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that carries them; the combo's saved `modePack`/`budgetCap` are used when the header is
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absent.
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| Header | Accepts | Effect |
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| :------------------- | :-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | :-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
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| `X-OmniRoute-Mode` | a preset alias (`fast`, `balanced`, `quality`, `cheap`, `reliable`, `offline`) or a raw pack name (`ship-fast`, `cost-saver`, `quality-first`, `offline-friendly`, `reliability-first`) | Overrides the scoring weights for this request. `balanced`/`default` force the default weights (no pack). Unknown values are ignored (config preserved). |
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| `X-OmniRoute-Budget` | a positive number (max USD per request) | Hard cost ceiling: candidates whose estimated cost exceeds it are filtered before selection, falling back to the cheapest healthy candidate if all exceed. Non-positive/garbage values are ignored. |
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```bash
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# Force the fastest profile and cap this request at $0.05
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curl -sS http://localhost:20128/v1/chat/completions \
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-H "Content-Type: application/json" \
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-H "X-OmniRoute-Mode: fast" \
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-H "X-OmniRoute-Budget: 0.05" \
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-d '{"model":"auto","messages":[{"role":"user","content":"hi"}]}'
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```
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Resolution is a pure function (`open-sse/services/autoCombo/requestControls.ts`); the
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resolved values feed the engine's existing `config.modePack` / `config.budgetCap` inputs.
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## All Routing Strategies
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OmniRoute's combo engine supports **18 routing strategies** (declared in `src/shared/constants/routingStrategies.ts` → `ROUTING_STRATEGY_VALUES`). The Auto Combo engine itself is exposed under the `auto` strategy; the others are available for persisted combos.
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| Strategy | Description |
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| :------------------ | :--------------------------------------------------------------------------------------------------------------------------- |
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| `priority` | First-target ordered list with explicit priority |
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| `weighted` | Weighted random by per-target weight |
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| `round-robin` | Cycle through targets in order |
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| `context-relay` | Hand off context across targets (long conversations) |
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| `fill-first` | Fill each target's quota before moving to next |
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| `p2c` | Power-of-2-choices random load balancing |
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| `random` | Uniform random selection |
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| `least-used` | Pick target with lowest current load |
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| `cost-optimized` | Minimize $ per request given catalog pricing |
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| `reset-aware` ⭐ | Prioritize by quota reset time — short reset windows ranked higher |
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| `reset-window` | Prefer targets whose quota window resets soonest |
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| `headroom` | Pick the target with the most remaining quota headroom |
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| `strict-random` | Random without deduplication of repeats |
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| `auto` | Use Auto Combo scoring (9-factor) — **recommended** |
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| `lkgp` | Last-Known-Good Path (sticky route to last successful target) |
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| `context-optimized` | Pick target with best fit for current context size |
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| `fusion` 🧬 | Fan out to a panel of models in parallel, then synthesize one answer via a judge (see below) |
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| `pipeline` | Run targets sequentially, threading each step's output into the next step's input; only the final answer is returned (#6396) |
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⭐ = New in v3.8.0 · 🧬 = New in v3.8.36
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## Fusion Strategy
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`fusion` is the one strategy that does **not** pick a single target. It fans the prompt
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out to **every panel model in parallel**, then a configurable **judge model** synthesizes
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a single final answer from all panel responses. Ported from upstream `decolua/9router`
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(OpenRouter's Fusion design); implementation in `open-sse/services/fusion.ts`.
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How it works:
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1. **Fan-out** — the prompt is sent to every panel model at once, forced non-streaming
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with tools stripped (the judge needs complete prose to synthesize).
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2. **Quorum-grace collection** — as soon as `minPanel` answers arrive, a short grace
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timer starts for the stragglers, then fusion proceeds with whatever was collected.
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This caps the slowest model's penalty on wall time, bounded by a hard timeout.
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3. **Judge synthesis** — panel answers are anonymized (`Source 1`, `Source 2`, … — so
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the judge weighs substance, not model brand) and handed to the judge, which analyzes
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consensus / contradictions / partial coverage / unique insights / blind spots, then
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writes **one** authoritative answer. The judge call keeps the client's original
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`stream` flag + tools, so streaming and downstream tool use still work.
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4. **Graceful degradation** — 0 panel answers → `503`; exactly 1 survivor → that answer
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is returned directly (nothing to fuse); a single-model panel answers directly.
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### Configuration
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Configured on the combo's `config` blob (no schema migration — it reuses the existing
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`combos` table):
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| Field | Type | Default | Purpose |
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| :--------------------------------------- | :------- | :---------------- | :-------------------------------------------------------------------------------------- |
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| `config.judgeModel` | `string` | first panel model | Model that synthesizes the final answer |
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| `config.fusionTuning.minPanel` | `number` | `2` | Successful answers required before the grace timer starts (clamped to `[2, panelSize]`) |
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| `config.fusionTuning.stragglerGraceMs` | `number` | `8000` | How long to wait for laggards once quorum is reached |
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| `config.fusionTuning.panelHardTimeoutMs` | `number` | `90000` | Absolute cap so one hung model can't stall the request |
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Defaults live in `FUSION_DEFAULTS` (`open-sse/services/fusion.ts`).
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### Example
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```bash
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curl -X POST http://localhost:20128/api/combos \
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-H "Authorization: Bearer <key>" \
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-H "Content-Type: application/json" \
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-d '{
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"name": "fusion-panel",
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"strategy": "fusion",
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"targets": [
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{ "model": "cc/claude-opus-4-7" },
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{ "model": "cx/gpt-5.5" },
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{ "model": "glm/glm-5.1" }
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],
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"config": {
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"judgeModel": "cc/claude-opus-4-7",
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"fusionTuning": { "minPanel": 2, "stragglerGraceMs": 8000, "panelHardTimeoutMs": 90000 }
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}
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}'
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```
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Then call it like any combo: `{"model":"fusion-panel","messages":[...]}`.
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## Virtual Auto-Combo Factory
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The Auto Combo engine doesn't require pre-defined combos. Instead, `open-sse/services/autoCombo/virtualFactory.ts` builds candidates on-the-fly:
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1. Pulls `getProviderConnections({ isActive: true })` (all enabled connections)
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2. Filters to those with valid credentials (API key or non-expired OAuth token via `hasUsableOAuthToken()`)
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3. Cross-references with `getProviderRegistry()` for model availability + pricing
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4. For each tuple `(provider, model, connection)`, builds a `VirtualAutoComboCandidate`
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5. Picks `connection.defaultModel` (or the registry's first model) as the dispatch target
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6. Scores each candidate using the 9-factor `scorePool()` and the variant's weight pack
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7. Returns the resulting in-memory `AutoComboConfig` for `handleComboChat()` — never persisted to DB
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This means **adding a new provider with `auto/*` enabled automatically expands the candidate pool** — no manual combo editing needed. The virtual combo is rebuilt per request, so newly-added or newly-healthy connections are picked up immediately.
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## Self-Healing
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- **Temporary exclusion**: Score < 0.2 → excluded for 5 min (progressive backoff, max 30 min)
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- **Circuit breaker awareness**: OPEN → auto-excluded; HALF_OPEN → probe requests
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- **Incident mode**: >50% OPEN → disable exploration, maximize stability
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- **Cooldown recovery**: After exclusion, first request is a "probe" with reduced timeout
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## Bandit Exploration
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5% of requests (configurable) are routed to random providers for exploration. Disabled in incident mode.
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## API
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There is **no dedicated `POST /api/combos/auto` endpoint** — Auto-Combo is consumed in two ways:
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1. **Zero-config (recommended):** Send any chat completion request with `model: "auto"` or `model: "auto/<variant>"`. The virtual factory builds the combo per request — no persistence, no API calls needed.
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2. **Persisted combo with `strategy: "auto"`:** Create a regular combo via `POST /api/combos` and set `strategy: "auto"` plus `config.auto.weights` / `config.auto.candidatePool`. The same scoring engine is used; the combo is stored in `combos` and reusable by ID.
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For discovery, `GET /api/combos/auto` lists every variant with its resolved candidate pool plus `context_length` / `max_output_tokens` — the MAX across the candidate pool's windows. Clients (e.g. the opencode plugin) must advertise these values instead of `0`: a zero context disables opencode's auto-compaction entirely, letting sessions grow until the gateway's history purge destroys context. MAX is safe to advertise because the auto-combo context pre-filter routes oversized requests to large-window candidates.
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```bash
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# Zero-config usage (no combo creation)
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curl -X POST http://localhost:20128/v1/chat/completions \
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-H "Authorization: Bearer <key>" \
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-H "Content-Type: application/json" \
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-d '{"model":"auto/coding","messages":[{"role":"user","content":"Hello"}]}'
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# Persisted auto combo via the regular combos endpoint
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curl -X POST http://localhost:20128/api/combos \
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-H "Content-Type: application/json" \
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-d '{"id":"my-auto","name":"Auto Coder","strategy":"auto","config":{"auto":{"candidatePool":["anthropic","google","openai"],"weights":{"quota":0.15,"health":0.3,"costInv":0.05,"latencyInv":0.35,"taskFit":0.1,"stability":0,"tierPriority":0.05}}}}'
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```
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### Auto router strategies
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Persisted `strategy: "auto"` combos can set `config.routerStrategy` (or legacy
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`config.auto.routerStrategy`) to one of:
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- `rules` — default weighted scoring
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- `cost` / `eco` — cheapest healthy provider
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- `latency` / `fast` — lowest p95 latency with reliability penalty
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- `sla-aware` / `sla` — prefer candidates that satisfy p95 latency, error-rate, and optional
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cost SLOs
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- `lkgp` — last known good provider first
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### Router strategies in detail
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The auto-combo engine exposes 5 pluggable **RouterStrategy** implementations that
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you can swap via `config.routerStrategy` (or the legacy `config.auto.routerStrategy`).
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Each strategy picks one provider from the candidate pool, given a `RoutingContext`
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(task type, tool/vision hints, token estimate, optional SLA policy, optional
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last-known-good provider).
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#### 1. `rules` (default) — 6-factor weighted scoring
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Wraps the existing scoring engine. Filters out `OPEN` circuit-breaker
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candidates, then runs `scorePool()` with the current task type and `getTaskFitness()`,
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picking the top-scoring provider.
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```ts
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class RulesStrategyImpl implements RouterStrategy {
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readonly name = "rules";
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readonly description =
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"6-factor weighted scoring: quota, health, cost, latency, taskFit, stability";
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select(pool, context) {
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const eligible = pool.filter((c) => c.circuitBreakerState !== "OPEN");
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const ranked = scorePool(
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eligible.length > 0 ? eligible : pool,
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context.taskType,
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undefined,
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getTaskFitness
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);
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return { provider: ranked[0].provider /* ... */ };
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}
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}
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```
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**When to use**: Default. Use when you want a balanced trade-off across all signals.
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**Alias**: `rules` (no alias)
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---
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#### 2. `cost` / `eco` — cheapest healthy provider
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Sorts the candidate pool by `costPer1MTokens` (ascending) and picks the cheapest.
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Filters out `OPEN` candidates first.
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```ts
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class CostStrategyImpl implements RouterStrategy {
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readonly name = "cost";
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readonly description = "Always selects cheapest available provider";
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select(pool, context) {
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const healthy = pool.filter((c) => c.circuitBreakerState !== "OPEN");
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const sorted = [...healthy].sort((a, b) => a.costPer1MTokens - b.costPer1MTokens);
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return { provider: sorted[0].provider /* ... */ };
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}
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}
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```
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**When to use**: Cost-sensitive workloads, batch processing, or background jobs.
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**Aliases**: `cost`, `eco`
|
||
|
||
---
|
||
|
||
#### 3. `latency` / `fast` — lowest p95 latency with reliability penalty
|
||
|
||
Sorts by `p95LatencyMs + (errorRate * 1000)`. The error-rate penalty ensures
|
||
unreliable providers are ranked lower even if their nominal latency is low.
|
||
|
||
```ts
|
||
class LatencyStrategyImpl implements RouterStrategy {
|
||
readonly name = "latency";
|
||
readonly description = "Prioritizes lowest p95 latency with reliability weighting";
|
||
|
||
select(pool, context) {
|
||
const healthy = pool.filter((c) => c.circuitBreakerState !== "OPEN");
|
||
const sorted = [...healthy].sort(
|
||
(a, b) => a.p95LatencyMs + a.errorRate * 1000 - (b.p95LatencyMs + b.errorRate * 1000)
|
||
);
|
||
return { provider: sorted[0].provider /* ... */ };
|
||
}
|
||
}
|
||
```
|
||
|
||
**When to use**: Latency-sensitive workloads like real-time chat, autocomplete, or
|
||
interactive coding assistants.
|
||
|
||
**Aliases**: `latency`, `fast`
|
||
|
||
---
|
||
|
||
#### 4. `sla-aware` / `sla` — latency/error/cost SLO compliance
|
||
|
||
Scores each candidate by how well it satisfies the configured SLO policy:
|
||
|
||
| Factor | Weight | Formula |
|
||
| --------------- | ------ | ------------------------------------------------- |
|
||
| Latency score | 35% | `threshold / max(value, ε)` |
|
||
| Error score | 35% | `threshold / max(value, ε)` |
|
||
| Health score | 15% | `1.0` (CLOSED) / `0.5` (HALF_OPEN) / `0.0` (OPEN) |
|
||
| Cost score | 10% | `threshold / max(value, ε)` or inverse normalized |
|
||
| Stability score | 5% | inverse normalized latency stddev |
|
||
|
||
When `hardConstraints: true`, candidates are sorted primarily by **violation score**
|
||
(how far they exceed any SLO), then by composite score. Otherwise it's just
|
||
the composite score.
|
||
|
||
```ts
|
||
class SLAStrategyImpl implements RouterStrategy {
|
||
readonly name = "sla-aware";
|
||
readonly description =
|
||
"Selects the provider most likely to satisfy latency, error-rate, and cost SLOs";
|
||
|
||
select(pool, context) {
|
||
// ... scores each candidate against policy: { targetP95Ms, maxErrorRate, maxCostPer1MTokens, hardConstraints }
|
||
}
|
||
}
|
||
```
|
||
|
||
**SLA fields** (set on the combo config):
|
||
|
||
```json
|
||
{
|
||
"strategy": "auto",
|
||
"config": {
|
||
"routerStrategy": "sla-aware",
|
||
"slaTargetP95Ms": 1500,
|
||
"slaMaxErrorRate": 0.05,
|
||
"slaMaxCostPer1MTokens": 5,
|
||
"slaHardConstraints": true
|
||
}
|
||
}
|
||
```
|
||
|
||
**When to use**: Production workloads with strict latency, error-rate, or cost budgets.
|
||
|
||
**Aliases**: `sla-aware`, `sla`
|
||
|
||
---
|
||
|
||
#### 5. `lkgp` — last known good provider first
|
||
|
||
Tries the **last known good provider** (if set) first, then falls back to the
|
||
`rules` strategy. Useful for session stickiness — the same provider handles
|
||
follow-up requests in a conversation.
|
||
|
||
```ts
|
||
class LKGPStrategyImpl implements RouterStrategy {
|
||
readonly name = "lkgp";
|
||
readonly description = "Tries last known good provider first, then falls back to rules";
|
||
|
||
select(pool, context) {
|
||
if (context.lkgpEnabled === false) {
|
||
return getStrategy("rules").select(pool, context);
|
||
}
|
||
|
||
if (context.lastKnownGoodProvider) {
|
||
const candidates = pool.filter(
|
||
(c) => c.provider === context.lastKnownGoodProvider && c.circuitBreakerState !== "OPEN"
|
||
);
|
||
if (candidates.length > 0) {
|
||
return { provider: candidates[0].provider /* ... */ };
|
||
}
|
||
}
|
||
|
||
// Fallback to rules strategy
|
||
return getStrategy("rules").select(pool, context);
|
||
}
|
||
}
|
||
```
|
||
|
||
**When to use**: Multi-turn conversations where you want the same provider to handle
|
||
follow-up requests (e.g., for caching, context continuity, or pricing consistency).
|
||
|
||
**Alias**: `lkgp` (no alias)
|
||
|
||
---
|
||
|
||
### Custom router strategies
|
||
|
||
You can register your own `RouterStrategy` implementation via the public API:
|
||
|
||
```ts
|
||
import {
|
||
registerStrategy,
|
||
type RouterStrategy,
|
||
} from "@omniroute/open-sse/services/autoCombo/routerStrategy";
|
||
|
||
class MyCustomStrategy implements RouterStrategy {
|
||
readonly name = "my-custom";
|
||
readonly description = "My custom routing strategy";
|
||
|
||
select(pool, context) {
|
||
// Your routing logic here
|
||
return {
|
||
provider: pool[0].provider,
|
||
model: pool[0].model,
|
||
strategy: this.name,
|
||
reason: "MyCustomStrategy: ...",
|
||
candidatesConsidered: pool.length,
|
||
finalScore: 1.0,
|
||
};
|
||
}
|
||
}
|
||
|
||
registerStrategy("my-custom", new MyCustomStrategy());
|
||
```
|
||
|
||
Then use it:
|
||
|
||
```json
|
||
{
|
||
"strategy": "auto",
|
||
"config": {
|
||
"routerStrategy": "my-custom"
|
||
}
|
||
}
|
||
```
|
||
|
||
---
|
||
|
||
### Router strategy selection guide
|
||
|
||
| Use case | Strategy | Reason |
|
||
| ----------------- | ----------- | ------------------------------------ |
|
||
| Balanced workload | `rules` | Default — considers all factors |
|
||
| Minimize cost | `cost` | Always picks cheapest |
|
||
| Minimize latency | `latency` | Picks fastest reliable provider |
|
||
| Strict SLOs | `sla-aware` | Filters by p95/error/cost thresholds |
|
||
| Multi-turn chat | `lkgp` | Session stickiness |
|
||
|
||
SLA-aware fields:
|
||
|
||
```json
|
||
{
|
||
"strategy": "auto",
|
||
"config": {
|
||
"routerStrategy": "sla-aware",
|
||
"slaTargetP95Ms": 1500,
|
||
"slaMaxErrorRate": 0.05,
|
||
"slaMaxCostPer1MTokens": 5,
|
||
"slaHardConstraints": true
|
||
}
|
||
}
|
||
```
|
||
|
||
## Task Fitness
|
||
|
||
30+ models scored across 6 task types (`coding`, `review`, `planning`, `analysis`, `debugging`, `documentation`). Supports wildcard patterns (e.g., `*-coder` → high coding score).
|
||
|
||
## Auto Variants Recap
|
||
|
||
Including the bare `auto` (default) plus the 6 `AutoVariant` values declared in `autoPrefix.ts`, there are **7 invokable model IDs**:
|
||
|
||
`auto`, `auto/coding`, `auto/fast`, `auto/cheap`, `auto/offline`, `auto/smart`, `auto/lkgp`
|
||
|
||
(`AutoVariant` itself enumerates 6 values; the 7th option is "no variant" — bare `auto` — handled by `parseAutoPrefix()` as `variant: undefined`.)
|
||
|
||
## How tiers fit Auto-Combo
|
||
|
||
The 12-factor scoring function (`open-sse/services/autoCombo/scoring.ts`) treats tier
|
||
membership as two signals: `tierPriority` (0.05) and `tierAffinity` (0.05). See the
|
||
canonical [scoring factor table](#how-it-works-persisted-auto-combos) above for the full
|
||
`DEFAULT_WEIGHTS` set — the per-pack overrides (ship-fast/cost-saver/quality-first/
|
||
offline-friendly) are listed in the "Weight profiles per pack" table.
|
||
|
||
Tier alone does **not** force Tier 1 first — if Tier 1 latency is bad or
|
||
cost-vs-quality is suboptimal, Tier 2 wins. To force tier ordering, use combo
|
||
strategy `priority` and arrange providers by tier.
|
||
|
||
To strongly favor Tier 1 (subscription), increase `tierPriority` weight:
|
||
|
||
```json
|
||
{
|
||
"strategy": "auto",
|
||
"config": { "auto": { "weights": { "tierPriority": 0.3, "costInv": 0.05 } } }
|
||
}
|
||
```
|
||
|
||
See `docs/marketing/TIERS.md` for tier definitions and provider classification.
|
||
|
||
## Testing & Coverage
|
||
|
||
### Deterministic routing-decision matrix (`npm run test:combo:matrix`)
|
||
|
||
`tests/integration/combo-matrix/*.test.ts` proves the routing **decision** of all 17
|
||
public strategies end-to-end through the real combo pipeline with a mocked upstream.
|
||
Coverage includes:
|
||
|
||
- All 18 `ROUTING_STRATEGY_VALUES` strategies (ordered, weighted, cost, context, fusion, …).
|
||
- `quota-share` (internal) end-to-end: DRR fairness + saturation deprioritization via the
|
||
real `selectQuotaShareTarget` seam (`registerQuotaFetcher` / `setLKGP` /
|
||
`__setHeadroomSaturationFetcherForTests`).
|
||
- `context-relay` universal-handoff coverage across every target count.
|
||
|
||
This suite runs in CI (`test:integration` job) with `--test-concurrency=1` and
|
||
`--test-force-exit` so it is deterministic and does not require live credentials.
|
||
|
||
### Gated live smoke (NOT in CI — real providers)
|
||
|
||
| Command | What it does |
|
||
| :------------------------------------- | :----------------------------------------------------------------------------- |
|
||
| `npm run test:combo:live` | In-process real routing with `RUN_COMBO_LIVE=1`; snapshots a live OmniRoute DB |
|
||
| `npm run test:combo:live:vps` | HTTP calls against a live OmniRoute server (set `COMBO_LIVE_BASE_URL`) |
|
||
| `npm run test:combo:live:vps:failover` | Same, with deliberate failover scenarios |
|
||
|
||
These smoke tests exercise the real wire path (combo → provider → completion). They are
|
||
intentionally excluded from CI because they require live credentials and VPS access.
|
||
|
||
---
|
||
|
||
## Files
|
||
|
||
| File | Purpose |
|
||
| :-------------------------------------------------------- | :------------------------------------------------------------------------- |
|
||
| `open-sse/services/autoCombo/scoring.ts` | 9-factor scoring function, `DEFAULT_WEIGHTS`, pool norm |
|
||
| `open-sse/services/autoCombo/taskFitness.ts` | Model × task fitness lookup |
|
||
| `open-sse/services/autoCombo/engine.ts` | Selection logic, bandit, budget cap |
|
||
| `open-sse/services/autoCombo/selfHealing.ts` | Exclusion, probes, incident mode |
|
||
| `open-sse/services/autoCombo/modePacks.ts` | 4 weight profiles (ship-fast, cost-saver, quality-first, offline-friendly) |
|
||
| `open-sse/services/autoCombo/autoPrefix.ts` | `auto/` prefix parser + 6 variants |
|
||
| `open-sse/services/autoCombo/virtualFactory.ts` | Builds in-memory `AutoComboConfig` from live connections |
|
||
| `open-sse/services/autoCombo/providerRegistryAccessor.ts` | Test hook for mocking provider registry |
|
||
| `src/shared/constants/routingStrategies.ts` | `ROUTING_STRATEGY_VALUES` (18 strategies) |
|
||
| `src/sse/handlers/chat.ts` | Integration: auto-prefix short-circuit |
|