Add model-router skill for cost-aware LLM selection

README.md

@@ -50,7 +50,7 @@ See [`integrations/README.md`](integrations/README.md), [`automations/README.md`
 ## Extensions Catalog
 
 <!-- BEGIN AUTO-GENERATED CATALOG -->
-This repository contains **2 marketplace(s)** with **50 extensions** (40 skills, 10 plugins).
+This repository contains **2 marketplace(s)** with **51 extensions** (41 skills, 10 plugins).
 
 ### large-codebase
 
@@ -69,7 +69,7 @@ OpenHands skills for interacting, improving, and refactoring large codebases
 
 Official skills and plugins for OpenHands — the open-source AI software engineer.
 
-**46 extensions** (38 skills, 8 plugins)
+**47 extensions** (39 skills, 8 plugins)
 
 | Name | Type | Description | Commands |
 |------|------|-------------|----------|
@@ -98,6 +98,7 @@ Official skills and plugins for OpenHands — the open-source AI software engine
 | learn-from-code-review | skill | Distill code review feedback from GitHub PRs into reusable skills and guidelines. Use when users ask to learn from co... | `/learn-from-reviews` |
 | linear | skill | Interact with Linear project management - query issues, update status, create tickets using the Linear GraphQL API. | — |
 | magic-test | plugin | A simple test plugin for verifying plugin loading. Triggers on magic words (alakazam, abracadabra) and returns a spec... | — |
+| model-router | skill | Recommend the most cost-efficient LLM for a given task category (research, bug fixing, planning, frontend, testing, b... | — |
 | notion | skill | Create, search, and update Notion pages/databases using the Notion API. Use for documenting work, generating runbooks... | — |
 | npm | skill | Handle npm package installation in non-interactive environments by piping confirmations. Use when installing Node.js ... | — |
 | onboarding | plugin | Assess repository agent-readiness across five pillars, propose high-impact fixes, and generate repo-specific AGENTS.m... | — |

marketplaces/openhands-extensions.json

@@ -590,6 +590,20 @@
                 "pull-request",
                 "iterate"
             ]
+        },
+        {
+            "name": "model-router",
+            "source": "./skills/model-router",
+            "description": "Recommend the most cost-efficient LLM for a given task category (research, bug fixing, planning, frontend, testing, bulk repetitive work) based on the OpenHands Index benchmark data. Use when picking a model, configuring a sub-agent, or optimizing cost vs. quality.",
+            "category": "productivity",
+            "keywords": [
+                "model",
+                "llm",
+                "cost",
+                "routing",
+                "benchmark",
+                "openhands-index"
+            ]
         }
     ]
 }

skills/model-router/README.md

@@ -0,0 +1,57 @@
+# model-router
+
+A small OpenHands skill that recommends the most cost-efficient LLM for a given
+task category, using benchmark data from the public [OpenHands
+Index](https://index.openhands.dev).
+
+## What it does
+
+When the agent (or user) needs to pick a model, this skill provides a quick
+lookup table mapping task type to:
+
+- **Cost pick** - best score-per-dollar on the Pareto frontier
+- **Balanced pick** - good score at moderate cost
+- **Premium pick** - top raw score, ignore cost
+
+Categories covered (matching the OpenHands Index):
+
+- Research / Information gathering
+- Bug fixing / Issue resolution
+- Planning / Architecture / Greenfield builds
+- Frontend / UI
+- Testing / Test generation
+- Bulk repetitive work (cheap reasoning at scale)
+
+## When it triggers
+
+This skill activates on keyword cues like "which model", "pick a model",
+"cost-efficient model", "best model for ...", or "model router". The agent can
+also load it on demand when it needs to recommend or switch models, for example
+when configuring a sub-agent or delegating a cloud conversation.
+
+## Example output
+
+If the user asks "which model should I use for deep research across multiple
+sites?", the agent (with this skill loaded) should answer with something like:
+
+> Use **Gemini-3.1-Pro** ($0.12 per task, score 76.4 on GAIA via OpenHands
+> Index). If you need the absolute best quality and don't mind paying ~6x more,
+> switch to GPT-5.5 ($0.74, 86.1). Source: https://index.openhands.dev/information-gathering
+
+## Why this exists
+
+LLM cost per task varies by 10x or more across the Pareto frontier. Defaulting
+to a single premium model for every step of an agent run leaves a lot of money
+on the table when cheaper models reach 90%+ of the quality on most subtasks.
+This skill encodes a few sensible defaults so the agent can route work to the
+right model without having to re-derive the tradeoff each time.
+
+## Caveats
+
+- Numbers are a May 2026 snapshot from index.openhands.dev. Re-check the index
+  before committing to a model for a long-running production job.
+- The benchmark measures full agent runs, not raw completions. For one-shot
+  classifications or short summaries, almost any capable cheap model is fine.
+- Whether your runtime can actually switch models mid-conversation depends on
+  how OpenHands is deployed (sub-agents, delegated cloud conversations, or just
+  the user choosing a model when starting a session).

skills/model-router/SKILL.md

@@ -0,0 +1,98 @@
+---
+name: model-router
+description: Recommend the most cost-efficient LLM for a given task category (research, bug fixing, planning, frontend, testing, bulk repetitive work) based on the OpenHands Index benchmark data. Use when the user asks "which model should I use", wants to pick a model, configure a sub-agent, route work to another LLM, or optimize for cost vs. quality.
+triggers:
+- which model
+- model selection
+- pick a model
+- model router
+- cost efficient model
+- cheapest model
+- best model for
+---
+
+# Model Router
+
+Pick the right LLM for the task instead of paying premium prices for every step.
+Recommendations below come from the public [OpenHands Index](https://index.openhands.dev)
+benchmark (May 2026 snapshot). For each category we list a **cost pick** (best
+score-per-dollar on the Pareto frontier), a **balanced pick**, and a **premium
+pick** (top raw score).
+
+If your runtime supports model switching (sub-agents, delegated cloud
+conversations, or just user choice), default to the cost pick and only escalate
+to balanced/premium when the task warrants it.
+
+## Quick decision table
+
+| Task type | Cost pick (cheap & good) | Balanced | Premium (top score) |
+| --- | --- | --- | --- |
+| Research / Information gathering | **Gemini-3.1-Pro** ($0.12, 76.4) | claude-opus-4-6 ($0.44, 80.0) | GPT-5.5 ($0.74, 86.1) |
+| Bug fixing / Issue resolution | **Minimax-2.7** ($0.18, 75.6) | claude-opus-4-6 ($0.77, 76.8) | GPT-5.5 ($1.52, 78.2) |
+| Planning / Architecture / New apps (greenfield) | **GPT-5.4** ($4.04, 56.2) | claude-opus-4-7 ($5.69, 56.2) | claude-opus-4-7 ($5.69, 56.2) |
+| Frontend / UI | **Gemini-3.1-Pro** ($1.24, 44.1) | claude-opus-4-6 ($2.37, 41.8) | claude-opus-4-7 ($2.83, 48.5) |
+| Testing / Test generation | **Minimax-2.7** ($0.13, 69.1) | claude-opus-4-6 ($0.43, 78.8) | GPT-5.5 ($0.92, 83.4) |
+| Bulk repetitive lifting (cheap reasoning at scale) | **DeepSeek-V3.2-Reasoner** ($0.57) | Minimax-2.7 ($0.13-0.18) | n/a - escalate if quality matters |
+
+Numbers are **average cost per problem (USD)** and **score** from the index.
+Lower cost and higher score are both better.
+
+## How to use this skill
+
+1. **Identify the task category** from the user request. Map it to a row above:
+   - "find/research/look up/answer with sources" -> Research
+   - "fix bug / failing test / SWE-bench style issue / debug" -> Bug fixing
+   - "design / plan / build new app or feature from scratch" -> Planning
+   - "build UI / page / component / styling" -> Frontend
+   - "write tests / increase coverage / add unit tests" -> Testing
+   - "rename across N files / run the same edit many times / mechanical refactor" -> Bulk
+
+2. **Default to the cost pick.** Tell the user (or pick programmatically) the
+   cost pick model, citing roughly how much you expect to spend per task.
+
+3. **Escalate when justified.** Switch to the balanced or premium pick if any
+   of these are true:
+   - The task is high-stakes (production bug, security fix, breaking change).
+   - The cost pick has clearly failed once on the same task.
+   - The user explicitly asked for the best possible quality.
+   - The task spans multiple categories (e.g., "design + build + test a new
+     service") - prefer a strong all-rounder like **claude-opus-4-7** or
+     **GPT-5.5**.
+
+4. **Mixed pipelines** are encouraged. Example flow for a feature request:
+   - Research existing code & docs -> Gemini-3.1-Pro
+   - Plan the change -> claude-opus-4-7
+   - Implement the fix -> claude-opus-4-6 or Minimax-2.7
+   - Generate tests -> claude-opus-4-6
+   - Repetitive lint/format/codemod cleanup -> DeepSeek-V3.2-Reasoner
+
+5. **Show your work.** When you recommend a model to the user, include:
+   - The chosen model and a one-line justification.
+   - Expected cost per task (from the table) and any quality tradeoff.
+   - A link to https://index.openhands.dev so they can verify or pick differently.
+
+## Heuristics & caveats
+
+- **Pareto frontier matters more than headline score.** A model that is 95% as
+  accurate at 20% of the cost is almost always the right starting point.
+- **Numbers age fast.** Treat the table as a current-as-of-May-2026 snapshot.
+  When in doubt, re-check the relevant category page on
+  https://index.openhands.dev before committing to a model for a long-running
+  job.
+- **One-shot vs. multi-turn.** The index measures agent runs, not raw
+  completions. If you only need a single classification or a short summary, the
+  cost gap shrinks and any capable cheap model is fine.
+- **Open vs. closed models.** Minimax-2.7, DeepSeek-V3.2-Reasoner, GLM-5/5.1,
+  Qwen3.6, and Kimi are open-weights options if self-hosting or data residency
+  matters. Gemini, GPT-5.x, and claude-opus are closed.
+- **Greenfield is expensive everywhere.** Even the cost pick is ~$4 per problem
+  because these are long, multi-step builds. Budget accordingly or scope down.
+
+## Category pages on the OpenHands Index
+
+- Issue Resolution: https://index.openhands.dev/issue-resolution
+- Greenfield: https://index.openhands.dev/greenfield
+- Frontend: https://index.openhands.dev/frontend
+- Testing: https://index.openhands.dev/testing
+- Information Gathering: https://index.openhands.dev/information-gathering
+- Overall leaderboard: https://index.openhands.dev/