# Surfaces

| Reference | What it covers |
| [Core configuration](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/surface-reference.md) | The fields every surface shares, no matter what else you add to it: name and enabled state, the listener and route it answers on, which client API formats it accepts, and identity pass-through. |
| [Providers](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/providers.md) | Connecting a surface to an LLM provider: the fields each provider type asks for and where to find the values, the parameter override policy, and how a call’s cost gets priced. |
| [Guardrails](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/guardrails.md) | Screening requests and responses for sensitive content: Prompt Guard’s regex and PII rules, Expert Witness safety classifiers, and the Judge/Jury reasoning-based checks. |
| [Routing and variants](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/routing-and-variants.md) | Sending different requests to different upstreams: content-based routing with the Decider, attribute-based routing rules, canary traffic splits, and the surface’s variant catalogue. |
| [Resilience and caching](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/resilience-and-caching.md) | Keeping a surface up and fast: failover to backup providers, load balancing across a pool, streaming passthrough, and caching repeated responses. |
| [Cost and usage limits](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/cost-and-usage-limits.md) | Controlling spend: request-rate limiting, cost tracking, hard per-stage usage limits, and alerts when spend or error rates cross a threshold. |
| [Server tools and modalities](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/server-tools-and-modalities.md) | Turning on optional capabilities beyond plain chat: governed web search and web fetch, context-window compression, document ingestion, and audio/image/realtime-voice input. |
| [IDE Surfaces](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/ide-surfaces.md) | Building a governed model menu for IDE AI clients: which surfaces appear in the catalogue, central and per-member sign-in, and per-model access policy. |

## Pages in this section
- [Core configuration](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/surface-reference.md): Field reference for the configuration shared by every LLM Surface and IDE Surface.
- [Providers](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/providers.md): Field reference for every supported provider type, where each provider's values come from, the parameter override policy, and how token pricing resolves from the model catalogue.
- [Guardrails](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/guardrails.md): Field reference for Prompt Guard, Expert Witnesses, Judge, and Jury, the four guardrail layers attachable to an LLM Surface.
- [Routing and variants](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/routing-and-variants.md): Field reference for the Decider (content-based routing and Mirror mode), attribute-based routing rules, canary splits, and the surface variant catalogue.
- [Resilience and caching](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/resilience-and-caching.md): Field reference for failover, weighted load balancing, streaming passthrough, and the response cache.
- [Cost and usage limits](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/cost-and-usage-limits.md): Field reference for rate limiting, cost tracking, per-stage usage limits, and breach/anomaly usage alerts.
- [Server tools and modalities](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/server-tools-and-modalities.md): Field reference for governed web_search/web_fetch tools, context-window compression, document ingestion, and the audio/image/realtime-voice input gates.
- [IDE Surfaces](/products/affinidi-trust-fabric/agent-stream/reference/surfaces/ide-surfaces.md): Field reference for the IDE Surface catalogue type, its catalogue members, central client sign-in, and per-member upstream auth.