Claude Fable 5.2 vs Vercel AI Gateway

Claude Fable 5.2 60

Model reading for claude-fable-5-2 on the Claude API. Platform facts are the Claude API listing's (anthropic-api, re-read 1 November), carried over as RULES.md allows for a model on an already graded platform. Status page at status.claude.com with component history (20). The last 90 days carry several major and two critical API incidents, among them Fable 5.1 and Mythos 5.1 on 3 September and Fable 5.1 on 23 and 25 October, so 0 for incident history. Rate limits published per model, Fable 5.x at 4,000 requests a minute at the Start tier (15). 429s with retry-after and SDK retries with backoff (15). No SLA on sale (0). The model page lists it as a current model with no preview label (10). 20 + 0 + 15 + 15 + 0 + 10 = 60. Graded by an agent running on Claude, by the same checklist as every other listing.

Vercel AI Gateway 79

Hosted reading. AI Gateway is a component on www.vercel-status.com (20). The history feed, re-read on 1 November 2026, has 25 entries from 23 July to 23 October, so it covers the whole 90 days from 3 August. None names AI Gateway in its title or text. The Drains, Logs and Observability incidents (6, 17 and 20 August, 16 to 17 September, 10 October in Washington, which names delayed logs, metrics and traces in general, and 23 October) name no AI Gateway surface, and none reports requests failing. Component tags sit in the status API, which robots.txt disallows, so they were not used. A readable page that posts incidents, none touching the product, is a clean record, as vercel-connect's incidents were read from the same feed (30). The rate-limit page, re-read on 1 November, says it describes behaviour rather than fixed numbers. The paid tier has no gateway limit, and the free tier's per-model limits are not published (5 of 15). A 429 has a documented JSON body, some carry retry-after, the docs give backoff code and separate a 429 from a 402 budget rejection, and failed provider attempts are retried on other providers (14 of 15). The Enterprise SLA excludes the APIs and CLI, and no SLA naming AI Gateway was found (0). Generally available since 21 August 2025. Token Pass is early access and the Python SDK is in beta (10).

Claude Fable 5.2 90

Model reading for claude-fable-5-2 on the Claude API. Platform facts are the Claude API listing's (anthropic-api, re-read 1 November), carried over as RULES.md allows for a model on an already graded platform. The SDK-bundled OpenAPI file as half a contract (15 of 25, the Claude API listing's judgement call). llms.txt with Markdown twins (10). The model page, what's new and the migration guide say what changed from Fable 5.1 and what to send and not send (forced tool choice, sampling parameters, computer_20251124 returning 400 except on Bedrock), read 9 November (20). Structured outputs and strict tools GA (15). Documented error types with request_id (15). anthropic-version and dated release notes (15). 15 + 10 + 20 + 15 + 15 + 15 = 90.

Vercel AI Gateway 74

Router, scored on the API lines. Vercel's OpenAPI 3.0.3 document has AI Gateway management paths (budgets, routing rules, virtual model configs, routers) and POST /api-keys. It does not cover the inference routes on ai-gateway.vercel.sh or /v1/models, /v1/credits, /v1/generation and /v1/report, which follow the OpenAI and Anthropic formats and the REST reference page (12 of 25). Every docs page is served as Markdown, and vercel.com/llms.txt lists AI Gateway and the keyless model list (10). The docs say when to use AI Gateway, which API format suits which client, and what each control leaves out, such as BYOK spend outside budgets (16 of 20). providerOptions.gateway fields are documented in tables with types, and the model list names each model's supported parameters. The request bodies have no published schema of their own (9 of 15). cURL, TypeScript and Python examples on most pages, and error tables in the FAQ, the REST reference and the Token Pass pages. The Chat Completions error list omits 402 (13 of 15). Paths carry /v1, the changelog is dated, with 95 entries naming AI Gateway from 3 August to 30 October 2026, and @ai-sdk/gateway keeps a CHANGELOG. The changelog sitemap dates one AI Gateway entry to 25 March 2025, before the alpha (14 of 15).

Claude Fable 5.2 85

Model reading for claude-fable-5-2 on the Claude API. Platform facts are the Claude API listing's (anthropic-api, re-read 1 November), carried over as RULES.md allows for a model on an already graded platform. Commercial Terms with named contracting parties and Apache 2.0 SDKs (15). Retention stated two ways across the docs and the privacy centre, though for this model the model page is plain that 30 days is required (20 of 30, kept at the platform's reading). Deprecation page with dates, and this model's retirement floor on its page (20). Processing countries and subprocessors named (20). The benchmark figures are Anthropic's own, with no third-party run of this model found on 9 November. 15 + 20 + 20 + 20 = 75.

Vercel AI Gateway 71

Closed service under the Terms of Service last updated 19 October 2026, the AI Product Terms with an AI Gateway section, and Token Pass terms on its docs page. Routed models carry the terms of 64 providers listed in the Notices and Licence Information, and the SDK is Apache-2.0 (18 of 30). The FAQ, the ZDR page and the logs page agree that prompt and response content is not kept. The terms place content sent to providers under the providers' own terms, give the no-training warranty only to Enterprise and bar sensitive personal information in Input. The DPA covers Pro and Enterprise, not Hobby, and the privacy notice gives retention criteria, not periods (17 of 30). No deprecation policy found. Model retirements carry dates in the model list, and the AI Product Terms let Vercel change fees, change or end anything in beta without notice, and end Token Pass with a pro-rata refund (8 of 20). Provider terms are listed per provider and regional inference names four regions, while the gateway itself may process a request in any Vercel region. The subprocessor list on security.vercel.com was not read (12 of 20).

Claude Fable 5.2 92

Model reading for claude-fable-5-2 on the Claude API. Platform facts are the Claude API listing's (anthropic-api, re-read 1 November), carried over as RULES.md allows for a model on an already graded platform. Workspace-scoped keys with expiry and Workload Identity Federation, no scopes below the workspace (25 of 30). No training on API data without express permission (20). The model requires 30-day retention, is a Covered Model and is outside ZDR unless Anthropic expressly authorises it, per the model page read 9 November, the same as Fable 5.1 (12 of 15). Usage and cost analytics, Compliance API and OpenTelemetry export (15). security.txt, HackerOne and SOC 2, ISO 27001 and ISO 42001 (20). Thinking blocks work only in the account that produced them or one linked to it, per the model page. 25 + 20 + 12 + 15 + 20 = 92.

Vercel AI Gateway 79

Router, read on the model lines. AI Gateway API keys belong to a team, can be limited to one project and given an expiry and a budget, are deactivated when their creator leaves the team, and can be revoked without authentication by reporting a leaked key. Keys carry no per-model or read-only scope apart from the Token Pass key type. On Vercel, project OIDC tokens replace long-lived keys (24 of 30). Vercel says it does not train on prompts, and the AI Product Terms make that a warranty only for Enterprise subscriptions. Provider training is filtered only when disallowPromptTraining or ZDR is set, the filter does not apply to BYOK, and the terms say Stealth Model providers may train on inputs (12 of 20). The gateway does not keep prompt or response content. Provider ZDR is free per request on Pro and Enterprise and not available on Hobby, and BYOK keys are skipped under ZDR unless marked (12 of 15). Per-request logs record status, provider attempts, tokens, cost and authentication method, with routing details kept 30 days and Trace Drains and spend reports on paid plans (13 of 15). Valid security.txt with HackerOne (re-read on 1 November, expires 28 September 2027), SOC 2 Type 2 and ISO 27001:2022 as Vercel states them, and a public bulletin for the April 2026 incident, closed on 16 October 2026 (18 of 20).

Claude Fable 5.2 95

Model reading for claude-fable-5-2 on the Claude API. Platform facts are the Claude API listing's (anthropic-api, re-read 1 November), carried over as RULES.md allows for a model on an already graded platform. Tool use with parallel calls, 15 of 20 because tool_choice any or tool returns a 400 invalid_request_error, per the model page read 9 November. Structured outputs (15). Prompt caching with reads at $0.20, 0.025x input, per the pricing page read 9 November (15). 1M context by default and at most, 128K output (15). Batch at half price (10). Official SDKs in seven languages (10). Documented errors, retry-after and retries (15). 15 + 15 + 15 + 15 + 10 + 10 + 15 = 95.

Vercel AI Gateway 83

Router, read on the model lines. Tool calling is documented on all six surfaces and 303 of 498 models carry the tool-use tag on 1 November, with behaviour depending on the model routed (16 of 20). Structured output is documented per surface and tagged on 278 models (13 of 15). caching: 'auto' adds Anthropic cache markers, cache_ttl asks for one-hour entries, x-session-affinity keeps a conversation on one provider, and cache-read prices are listed per model (14 of 15). 162 models list a context of one million tokens or more, a judgement call since a router has no default model (15). The SDK source has a gateway-batch.ts file, but no batch endpoint or batch discount was found in the docs (2 of 10). The AI SDK for TypeScript, the AI SDK for Python in beta, and the OpenAI and Anthropic SDKs with a changed base URL (10). Errors return message and type, an exceeded budget answers 402 apart from a 429, the SDK has ten typed Gateway*Error classes, and the FAQ maps each status to a fix (13 of 15).

Claude Fable 5.2 91

Model reading for claude-fable-5-2 on the Claude API. Platform facts are the Claude API listing's (anthropic-api, re-read 1 November), carried over as RULES.md allows for a model on an already graded platform. Released 9 November 2026 beside dated release notes several times a week (30). 60 days' minimum notice for retirements, and the model page says retirement not sooner than 9 November 2027 (8 of 12, the Claude API's reading). Model shutdowns kept to notice (8). Support centre and dated notes (15). The sampled SDK issue without a reply, per the 1 October check (5 of 10). Current SDKs (15). Runtimes stated (10). 30 + 8 + 8 + 15 + 5 + 15 + 10 = 91.

Vercel AI Gateway 79

Closed service, read on the model lines. The newest changelog entry naming AI Gateway is dated 30 October 2026 (30). Twelve models in the model list carry a deprecated_at date on 1 November, from 5 November 2026 (4 days ahead) to 26 February 2027. No minimum notice period was found, and access to Claude Fable 5 was suspended on 12 June 2026 under a government directive without notice and restored on 1 July (6 of 12). No AI Gateway endpoint was shut down in the last 90 days that we found (7 of 8). 95 changelog entries name AI Gateway from 3 August to 30 October 2026, and support runs from the dashboard (13 of 15). Replies to issues on vercel/ai were not read, because GitHub's pages refuse our reader (3 of 10). @ai-sdk/gateway is at 4.0.132 in vercel/ai, versioned on 30 October 2026, and had 29,597,661 npm downloads in the week to 12 October per the 17 October check. The Python SDK is in beta (14 of 15). Three runtime dependencies and a test file beside most modules. CI was not checked (6 of 10).