Define comparison criteria
The work assignment is to classify models by quality, speed, cost and task. Define purpose, owner and permitted operating boundary before the first test.
The domain review baseline covers a fixed test sample and currently verified model and price data. Assumptions and missing information remain visible in the result.
Compare using the same task
- Select a fixed sample of intended tasks and define domain-specific assessment criteria.
- Record available models and relevant pricing information from official sources with a review date.
- Test candidates with identical inputs and record quality, speed and cost assumptions.
- Explain the selection for the specific purpose and define when it should be reviewed again.
Document the selection rationale
A comparison record contains identical inputs for each candidate, expert assessment of answers, measured completion times and dated cost assumptions. The weighting of criteria is traceable.
Avoid: old model names or benchmark scores treated as permanent truth. Without current model and pricing data or a representative work sample, no reliable winner can be established for business use.
Model selection: September 2026
Anthropic’s current model overview lists Fable 5.1 alongside Opus 5, Sonnet 5 and Haiku 4.5. Choose according to task, achievable quality, rework, runtime and cost. The dedicated Fable 5.1 article explains how to test a demanding part of a process against the existing solution. A model name alone is not a general procurement recommendation.
Decision matrix
| Decision point | Proceed when | Stop when |
|---|---|---|
| Comparison baseline | Documented: a fixed test sample and currently verified model and price data. | Scope, data or accountability remains unresolved. |
| Task test | A comparison record contains identical inputs for each candidate, expert assessment of answers, measured completion times and dated cost assumptions. The weighting of criteria is traceable. | There is only an unevaluated demo without acceptance evidence. |
| Decision boundary | Owner, approval, fallback and next review date are defined. | Avoid: old model names or benchmark scores treated as permanent truth. Without current model and pricing data or a representative work sample, no reliable winner can be established for business use. |
Keep it verifiable
Primary sources
- Claude SonnetSource checked:
- Claude EnterpriseSource checked:
- Anthropic: commercial data and trainingSource checked:
- Anthropic: Remote MCP connectorsSource checked:
- Anthropic: Claude model overviewSource checked:
- Anthropic: Claude API pricingSource checked:
- Claude Fable 5.1 model overviewSource checked:
- Claude models overviewSource checked:
