# Sieve documentation > Documentation for Sieve decision models and the public API. ## API contracts - [Combined public OpenAPI JSON](https://docs.sieve.one/openapi.json): generated from the backend-owned public Decisions and System One contracts. - [API overview](https://docs.sieve.one/api-reference): authentication, rate limits, error envelopes and interactive sandbox requests. ## Pages - [Introduction](https://docs.sieve.one): Sieve decision models behind a TypeSafe-compatible API. Send content and typed questions, get calibrated probabilities back. - [API overview](https://docs.sieve.one/api-reference): Authentication, rate limits and the generated public API reference. - [/v1/decisions](https://docs.sieve.one/api-reference/decisions): POST /v1/decisions, the OpenAI-style route, generated from the backend OpenAPI contract. - [System One](https://docs.sieve.one/api-reference/system-one): POST /v1/systemone and GET /v1/models, generated from the backend OpenAPI contract. - [Credits](https://docs.sieve.one/billing/credits): How prepaid credits work. You top up a balance and usage draws it down. - [Invoices and tax](https://docs.sieve.one/billing/invoices-and-tax): GST and tax IDs, invoices and credit notes, and how Indian and overseas customers are billed. - [Pricing](https://docs.sieve.one/billing/pricing): Modelled per-token prices for the Sieve decision models. Output tokens are free. Final prices follow benchmarking. - [Auto cascade](https://docs.sieve.one/decisions/auto-cascade): How sieve-auto works. It answers with the 4B model, then asks 31B only the questions that are unsure. - [Confidence](https://docs.sieve.one/decisions/confidence): What the confidence values mean, how they are computed, and how to use them to route uncertain answers to review. - [Errors](https://docs.sieve.one/decisions/errors): Every status code the decision API returns, with the exact response bodies, headers and retry guidance. - [Limits](https://docs.sieve.one/decisions/limits): Size, count and request-shape limits for the decision API, and what happens when you go over. - [Question types](https://docs.sieve.one/decisions/question-types): The three question types for decisions (yes/no, choice, score) and what each returns. Sieve never generates text. - [Assurance](https://docs.sieve.one/enterprise/assurance): Audit log, calibration and drift reports for your decisions, with a tamper-evident record that holds no content. - [Sieve Foundry](https://docs.sieve.one/enterprise/foundry): Prepare datasets, train private decision adapters and deploy evaluated models. - [Regions](https://docs.sieve.one/enterprise/regions): Where decisions run, how to pin a region, and where records are kept. - [Self-hosting](https://docs.sieve.one/enterprise/self-hosting): Run Sieve in your own environment with Sieve Vault, and evaluate the Vault bundle before a full install. - [Vault install](https://docs.sieve.one/enterprise/vault-install): Install Sieve Vault, the self-hosted Sieve container, in your own Kubernetes cluster. Air-gapped, signed images, offline licence. - [Sign-in and account security](https://docs.sieve.one/get-started/account-security): Sign up and sign in to the console, reset a password, and protect your account with two-factor authentication and passkeys. - [Authentication and keys](https://docs.sieve.one/get-started/authentication): How API keys work, how to send them, and what a 401 looks like. - [Delete or transfer](https://docs.sieve.one/get-started/delete-or-transfer): Schedule organisation or account deletion, cancel during the grace period, and understand retained records. - [Export your data](https://docs.sieve.one/get-started/export-your-data): Download a ZIP of your organisation's or your own account data from the console. - [Your first decision](https://docs.sieve.one/get-started/first-decision): A request with all three question types, and how to read each answer. - [Notifications](https://docs.sieve.one/get-started/notifications): What the console tells you, who in your organisation gets each notice, and which emails you can turn off. - [Organisations and members](https://docs.sieve.one/get-started/organisations): Who can see and do what in the console. Admins and members, invites, and what happens when someone is removed. - [Quickstart](https://docs.sieve.one/get-started/quickstart): Make your first decision with the TypeSafe SDK pointed at Sieve. Only the base URL and the key change. - [Get help](https://docs.sieve.one/get-started/support): Open a support ticket from the console, report a security issue, ask for higher limits, or write to support@sthanika.ai. - [Usage and exports](https://docs.sieve.one/get-started/usage): Explore requests, tokens and organisation spend across UTC date ranges. - [Billing basics](https://docs.sieve.one/guides/billing-basics): What a request costs, how the prepaid balance pays for it, and where to see your spend. - [Errors and retries](https://docs.sieve.one/guides/errors-and-retries): Which errors to retry, how long to wait, and how to make a retry safe with an idempotency key. - [Fine-tune a model with Foundry](https://docs.sieve.one/guides/fine-tuning): Prepare labelled examples, train a private adapter on Sieve-4B, check it against the base model, deploy it and call it as ft:. - [Playground](https://docs.sieve.one/guides/playground): Build a decision in the console without writing code, see the answer, and copy it as code. - [Rate limits and quotas](https://docs.sieve.one/guides/rate-limits-and-quotas): How request, token and daily limits work, how to read the rate-limit headers, and what to do when you hit one. - [Route uncertain answers to review](https://docs.sieve.one/guides/route-uncertain-answers): Act on confident answers automatically and send the doubtful ones to a person, using confidence for choice and score questions and the probability for yes/no. - [Migrate from Jev](https://docs.sieve.one/migrate-from-jev): How to move from TypeSafe (Jev) to Sieve. Most code changes are the base URL and the key. - [Model cards](https://docs.sieve.one/model-cards): One card per Sieve model, with the base model, limits, calibration, benchmarks and licence. - [Sieve-0.8B](https://docs.sieve.one/model-cards/sieve-0.8b): Model card for Sieve-0.8B, a small decision model. It returns probabilities for typed questions and does not generate text. - [Sieve-27B](https://docs.sieve.one/model-cards/sieve-27b): Model card for Sieve-27B (v1), a large decision model. It returns probabilities and does not generate text. - [Sieve-27B-v2](https://docs.sieve.one/model-cards/sieve-27b-v2): Model card for Sieve-27B-v2, a large fully fine-tuned decision model with per-category calibration. It returns probabilities and does not generate text. - [Sieve-2B](https://docs.sieve.one/model-cards/sieve-2b): Model card for Sieve-2B (v1), a small decision model. It returns probabilities for typed questions and does not generate text. - [Sieve-2B-v3](https://docs.sieve.one/model-cards/sieve-2b-v3): Model card for Sieve-2B-v3, a small decision model with per-category calibration. It returns probabilities and does not generate text. - [Sieve-31B](https://docs.sieve.one/model-cards/sieve-31b): Model card for Sieve-31B, the accuracy-tier decision model. It returns probabilities for typed questions and does not generate text. - [Sieve-4B](https://docs.sieve.one/model-cards/sieve-4b): Model card for Sieve-4B, the hosted low-cost decision model. It returns probabilities and does not generate text. - [Sieve-9B](https://docs.sieve.one/model-cards/sieve-9b): Model card for Sieve-9B (v1), a mid-size decision model. It returns probabilities and does not generate text. - [Sieve-9B-v2](https://docs.sieve.one/model-cards/sieve-9b-v2): Model card for Sieve-9B-v2, a mid-size decision model with per-category calibration. It returns probabilities and does not generate text. - [Sieve-Vision-4B](https://docs.sieve.one/model-cards/sieve-vision-4b): Model card for Sieve-Vision-4B, a vision decision model for multiple-choice questions about images. It returns probabilities and does not generate text. - [Acceptable use](https://docs.sieve.one/policies/aup): What you may and may not do with the Sieve API. - [Data retention](https://docs.sieve.one/policies/data-retention): We don't store your content. What we keep, for how long, and what Vault customers keep. - [Privacy Policy](https://docs.sieve.one/policies/privacy): What personal data Sieve collects, why, who we share it with, and your rights under Indian law. - [Security](https://docs.sieve.one/policies/security): How Sieve protects keys and traffic, and what Vault adds. - [Master Customer Agreement](https://docs.sieve.one/policies/terms): The agreement between Sieve AI and its customers for the console, API, playground and documentation. - [SDKs](https://docs.sieve.one/sdks): Use the TypeSafe Python and JavaScript SDKs with Sieve. Install, configure the base URL, key and model, and set timeouts, retries and compression.