Current limits and honest boundaries

API limitations

• Stable public compatibility is OpenAI-shaped Chat Completions, not the complete OpenAI platform.
• Responses, native Gemini, files, batches, fine-tuning, realtime, and legacy completions are not product-key surfaces.
• Native Anthropic Messages is provider-specific and does not translate the current NanoGPT/AIsa OpenAI-wire pool.
• Embeddings, image generation, audio, rerank, and moderation routes are registered but do not have a verified stable end-to-end product path.
• The developer message role and many newer Chat parameters are not forwarded.
• Full multi-turn tool-call compatibility is incomplete because assistant tool_calls are not preserved on the follow-up request.
• Structured output repair is best effort; applications must validate JSON themselves.
• Non-admin /v1/models is intentionally opaque and returns auto rather than the full internal registry.
• Settings BYOK is limited: detach and enable-toggle semantics are not enforced end to end, and attached credentials do not bypass Singular credit billing.

Payment limitations

• x402 and MPP default off and require a live deployment configuration and healthy verifiers.
• Payment requests require an explicit model and non-streaming request.
• Native Anthropic Messages and Responses cannot be paid through these per-call paths.
• Current x402 EVM upto behavior needs alignment with the current Permit2-based specification before release.
• MPP imr* methods are Singular-specific extensions with no published first-party client in this repository.
• No current test proves a real wallet → live facilitator/on-chain settlement → inference → receipt round trip; unit tests mock external settlement.
• Per-call payment is not a key-balance or reseller-wallet top-up and has no documented automatic-refund guarantee.

App limitations

• File attachments can be selected and previewed, but the active thread stream currently sends an empty attachment list; file bytes do not reach inference.
• Voice UI records elapsed time and submits a text placeholder rather than audio content.
• Space asset creation stores metadata and a placeholder URL; it is not a complete upload/retrieval pipeline.
• Media 'Regenerate' is currently a UI stub.
• Message likes and Library pin state are not fully account-synced.
• Consumer funding history remains empty when no safe key-scoped source exists.
• Account export downloads JSON immediately; it is not a ZIP delivered by email.
• Anonymous guest issuance requires Turnstile integration in production and should not be advertised as universally available until the active deployment includes that UI path.

Catalog limitations

The storefront feed is reliable for model ID, provider/name presentation, positive retail prices, and positive context values. Missing price, modality, BYOK, capability, and latency fields may be normalized or defaulted. Do not use them as definitive model capability evidence.

Release principle

Documentation follows verified behavior, not aspirational route names. A feature should move out of this page only after source wiring, contract tests, and a live smoke agree.