Cerebras Inference vs Cloudflare Workers AI

Cerebras Inference

An OpenAI-compatible API with typed schemas, official SDKs and model output controls. Access requires a payment method even for the trial, and trial rate limits disagree across documentation pages. Shared-model availability and dedicated-model availability differ.

Cloudflare Workers AI

Per-model prices, rate limits and JSON Schemas are public, 10,000 neurons a day are free, and x402 payment is in beta on /ai/run for four models. No SLA was found, three models moved to paid-only access on 28 July 2026 with no notice, and several docs pages still use a model retired in May.

Cerebras Inference

1. Set CEREBRAS_API_KEY and use https://api.cerebras.ai/v1 with an OpenAI-compatible client.
2. Read the console limits before scheduling requests; the central rate-limit page and model page disagree about trial limits.
3. Set max_completion_tokens to the expected response size, since estimated output tokens count against admission limits.
4. Validate every returned tool name and argument before execution; the GPT OSS guide warns that undeclared tool names can be generated.

Cloudflare Workers AI

1. Check the model page before calling. Seven models need Workers Paid or AI Gateway credits and return 403 with code 5035 on the Free plan
2. Read the internal code on a 429. 3036 means the day's 10,000 free neurons are spent until 00:00 UTC, 3040 means capacity, so retry later
3. Set options.rejectIfBusy to fail fast, or add ?queueRequest=true for the batch route when the answer can wait
4. Send the same x-session-affinity value on every turn of a session to reach the prefix cache and the cached-input price
5. Keep paid frontier models under 20 requests a minute per model, or 50 with prepaid AI Gateway credits