ModelSpec is an analysis of alternatives for AI models: it decides which models fit a job from your requirements, sourced benchmarks and real cost, and shows its work.
General assistant, balanced
Find an active assistant that balances how people rate its responses against task cost.
Worked example as of 2026-09-23, from the public data image.
Response quality first, cost as a real second term.
Requirements
model.class = text-generator: A conversational assistant needs a text-generating model.model.lifecycle = active: An active model is still supported by its lab or provider.
Preferences
chat_preference: Prefer assistants whose open-ended responses people rate more highly.-offering.cost_per_task: Among strong assistants, prefer the cheaper task.
Applied template spec
spec_version- 1
where- model.class = text-generator
- model.lifecycle = active
optimizeweightschat_preference- 0.6
-offering.cost_per_task- 0.4
Worked answer
Decision status: partial.
Tied on the evidence
anthropic/claude-opus-5-5google/gemini-3-8-flashgoogle/gemini-3-7-flashqwen/qwen3-8-max-0902openai/gpt-6-solxai/grok-4-7
probability bands: a model joins the leader when P(its score >= the leader's) >= 0.25 under the score posteriors; a weighted capability with an 80% interval wider than 2.8 is not enough evidence
Tie-breakers describe members of the tie. They do not establish a winner.
- Most independently measured tie-breaker: google/gemini-3-8-flash
This is a partial answer. Unknown facts or missing objective evidence can leave eligible candidates unranked.
probability bands: a model joins the leader when P(its score >= the leader's) >= 0.25 under the score posteriors; a weighted capability with an 80% interval wider than 2.8 is not enough evidence
Score and score interval use the objective's dimensionless normalised units. Cost per task is for the engine-selected offering and the applied spec's task size. When task size is omitted, the engine uses its documented default. P(best) is the engine probability. Unavailable means the engine did not return a value. Thin evidence is undetermined and is not a recommendation.
Best band
| Model | Score | Score interval | P(best) | Cost per task, USD | Capability estimates and intervals |
|---|---|---|---|---|---|
anthropic/claude-opus-5-5 | 0.846914 | [0.703041, 0.990787] | 0.4140625 | 0.24 |
|
openai/gpt-6-sol | 0.790483 | [0.64661, 0.934356] | 0.20703125 | 0.12 |
|
qwen/qwen3-8-max-0902 | 0.799797 | [0.655924, 0.94367] | 0.19140625 | 0.104 |
|
xai/grok-4-7 | 0.745338 | [0.601465, 0.889211] | 0.07421875 | 0.104 |
|
google/gemini-3-8-flash | 0.822556 | [0.7976, 0.847512] | 0.0703125 | 0.045 |
|
google/gemini-3-7-flash | 0.813658 | [0.788701, 0.838614] | 0.04296875 | 0.045 |
|
Rest band
| Model | Score | Score interval | P(best) | Cost per task, USD | Capability estimates and intervals |
|---|---|---|---|---|---|
meta/muse-spark-1-3 | 0.765089 | [0.7325, 0.797678] | 0.0 | 0.067 |
|
zhipu/glm-5-3 | 0.758923 | [0.736209, 0.781637] | 0.0 | 0.0736 |
|
google/gemini-3-1-pro-preview | 0.701498 | [0.680513, 0.722483] | 0.0 | 0.128 |
|
meta/muse-spark-1-1 | 0.699813 | [0.671785, 0.727841] | 0.0 | 0.067 |
|
anthropic/claude-opus-4-6 | 0.691491 | [0.671096, 0.711887] | 0.0 | 0.3 |
|
google/gemini-2-5-flash | 0.69117 | [0.668829, 0.713511] | 0.0 | 0.022 |
|
google/gemini-3-5-flash | 0.683543 | [0.662558, 0.704528] | 0.0 | 0.096 |
|
zhipu/glm-5-2 | 0.679011 | [0.656296, 0.701725] | 0.0 | 0.0736 |
|
anthropic/claude-opus-4-7 | 0.676242 | [0.655258, 0.697227] | 0.0 | 0.3 |
|
anthropic/claude-opus-5 | 0.65577 | [0.634786, 0.676755] | 0.0 | 0.3 |
|
openai/gpt-5-4 | 0.655352 | [0.634956, 0.675747] | 0.0 | 0.16 |
|
openai/gpt-5-6-sol | 0.654065 | [0.63276, 0.67537] | 0.0 | 0.24 |
|
deepseek/deepseek-v4-pro | 0.62854 | [0.605826, 0.651254] | 0.0 | 0.06864 |
|
anthropic/claude-fable-5 | 0.522509 | [0.501524, 0.543494] | 0.0 | 0.6 |
|
anthropic/claude-fable-5-1 | 0.485654 | [0.463682, 0.507627] | 0.0 | 0.6 |
|
openai/gpt-6-astra | 0.381863 | [0.35788, 0.405845] | 0.0 | 0.6 |
|
Unknown requirements
Some candidates may qualify. Missing facts:
chat_preferenceoffering.cost_per_task
Engine warnings
- not_separable
Omitted result rows: models 10; offerings 18. The bands above include all ranked models.
Decision dec_a6d258fd73f7d9848e50fa39 on public snapshot snap_05a963d2477ac2fb.
What this template teaches
A 60/40 blend lets a large price gap overturn a small quality lead.
The live board uses current data. Its answer can change as evidence changes.
Human lookup is free on Decide. CLI, API, and MCP access requires a key. Access and pricing.