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Model SelectionLLMEnterprise AIPlatform

Choosing the Right AI Model: Why One Size Doesn't Fit All

10 February 20267 min read

No single model is best for every task. Enterprise automation works best when the right model is used for the right job — balancing cost, accuracy, speed, and where your data can run (cloud vs on-premise). Here is a practical decision framework and how we apply it.

When to use which model

Coding and tool-heavy tasks: GPT-5.3-Codex excels at long-running agentic coding, debugging, and tool use with interactive steering. Use it where execution and iteration over code or scripts are central.

Long-context reasoning: Claude Opus 4.6’s 1M-token context and adaptive thinking suit deep analysis over large documents (contracts, compliance, due diligence). Use it when a single decision needs the full context in one place.

Vision and multimodal: Google Vision API and Vertex AI Vision (and Gemini where relevant) are the go-to for image and video understanding — defect detection, shelf analysis, document capture, occupancy. Use them when the primary input is pixels, not text.

On-premise and open-weight: When data cannot leave your environment, we use open-weight models hosted on your infrastructure, often sourced and evaluated via HuggingFace. Trade-off is typically cost and control vs frontier capability.

Cost vs accuracy vs speed

Larger frontier models (GPT-5.3-Codex, Opus 4.6) offer the best quality and reasoning but at higher cost per token. Smaller or specialised models (e.g. Codex-Spark, smaller open-source) are faster and cheaper but may need more guardrails or human checks. Our platform routes by task type: simple extraction or classification can use a smaller model; complex reasoning or long context uses a frontier model. That keeps quality high where it matters and cost down where it doesn’t.

How ConvertToAI’s intelligence layer works

Our orchestration layer doesn’t fix a single model for everything. We maintain a model router that selects the best model for each task based on input type (text, image, document), required context length, latency requirements, and your compliance constraints (e.g. on-prem only). So one workflow might use Vision for document ingestion, Opus 4.6 for contract analysis, and a smaller model for routing and logging. You get the right tool per step. For more on the architecture, see our platform overview.

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