litellm/litellm-rust/crates/inference-messages/AGENTS.md

• Shared base and layering rules: ../inference/AGENTS.md
• This crate owns provider-independent Messages call orchestration: the entrypoint, call envelopes, provider selection, credential resolution, transport coordination, hooks, and stream lifecycle
  • shared API data contracts belong in litellm-llms-types::formats::messages
  • adapter contracts and execution inputs in llms/src/base_llm/messages
  • provider implementations in llms/src/<provider>/messages
• Select concrete provider adapters and invoke their contracts
  • delegate authentication policy, beta selection, payload rewriting, and response interpretation to those adapters
  • keep provider policy out of request preparation and transport handlers
  • calling a concrete provider helper for every provider is still a policy dependency
• Route types such as MessagesCall, provider calls, and response wrappers containing live streams describe execution. Reuse the shared Messages payload types inside them instead of defining another request or response schema here
• The route returns litellm_host::call::CallOutput: a completed response, or a stream head and chunks
• Per-call dependencies are grouped in litellm_inference::context::CallContext. handler::execute explicitly sequences the provider call build in Python's handler order, cache lookup, provider execution, result acceptance (CallContext::result_ready), and cache storage
• Preserve the order of validation, normalization, caller-requested parameter removal, and provider transformation when that order affects observable behavior
• Test provider dispatch, auth precedence, header handling, transformations, and responses through behavior, not source structure