Your decisions, running in production.
Sutro is a platform for optimizing and running consistent AI Functions.
Upload an unlabeled dataset, add your feedback on the hardest cases, and Sutro engineers a prompt that reliably executes your task using off-the-shelf models.
Is this hacker news post related to aviation?
Sutro can now generalize the rules based on your feedback.
What is an AI Function?
A reliable AI Function repeatedly and consistently makes the same decisions as a human expert would on a given task.
Examples of AI Functions customers are building
Classifier
Score a lead based on a ideal customer profile rubric.
Judge
Give pass or fail assignments on agent traces.
Extractor
Remove personally identifiable information from medical records.
Entity resolver
Determine whether two businesses are the same.
Matcher
Determine whether a candidate is a good fit for a role.
Router
Send support tickets to the right team or person.
Relevance Judge
Determine whether a search result is relevant to a given query.
Intent Classifier
Cluster user intents within agent interactions.
Building an AI Function isn’t about scaling general intelligence. It’s about teaching a model exactly how your organization wants a task performed.
How are Sutro Functions run?
AI Functions can be run continuously as new inputs arrive, or in batch to transform large datasets all at once.
Functions can be run using your own model subscriptions, or using Sutro's cost-effective batch inference service.
Sutro Functions improve over time
Return any time to learn from new data, or optimize newly released models.
In production today
Sutro is powering critical, production AI Functions for many happy customers today, often in environments with strict data privacy and security requirements.
Who is Sutro for?
Applied AI teams
Agents, evals, matchers, and other production AI workflows.
Data & ML engineers
Data enrichment, entity resolution, and extraction tasks.
AI training data teams
Dataset filtering, labeling, tagging, and quality assurance.
Request customer case studies →“Sutro saves our team countless hours, and it gives us the invaluable ability to measure, optimize, and prevent regressions against our domain expertise. It’s a must-have for serious AI developers.”
Simple pricing
$500 / month
(includes $100/mo inference credits)Enterprise and self-hosted plans are tailored to your needs and scale.
Contact us for enterprise pricing →Batch inference
Machine-time pricing means you only pay for the compute your workload actually consumes.
Frequently asked
Is this an evals product?
Yes and no. Sutro helps evaluate quality and reliability, but unlike other evals products, it directly shapes model or agent behavior from feedback, rather than just monitoring.
Can Sutro use image inputs and other modalities? Can it call tools?
Yes. Sutro supports images, PDFs, and web search capabilities today. Additional modalities and custom tool calling are available on a per-request basis.
What models does Sutro Functions use?
Functions are model-agnostic, and we support a mix of open-source and proprietary models. Small, open-source models commonly outperform larger proprietary models when running AI Functions. Sutro helps automatically find the best model for your needs.
Can I self-host Sutro? Do you support BYOC and BYOK?
Yes. Sutro can be managed as SaaS or entirely self-hosted. You can bring your own provider keys and cloud credentials in either case.
How does Sutro compare to prompt engineering, fine-tuning, or RL?
Sutro is designed to be more robust, accurate, and scalable than prompt engineering, and more data efficient, portable, and re-trainable than fine-tuning or RL. We encourage you to try it out and see for yourself!