buildRequest now tracks a source-index → built-message-index mapping
during the role-merge pass, then uses the mapping to attach
cache_control: {type: ephemeral} markers at the positions indicated by
Request.CacheHints. The last tool, the last system part, and the last
non-system message each get a marker when the corresponding hint is set.
Covers the merge-induced index drift that would otherwise cause the
breakpoint to land on the wrong content block when consecutive same-role
source messages are combined into a single Anthropic message with
multiple content blocks.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Switches buildRequest to emit anthReq.MultiSystem instead of anthReq.System
whenever a system message is present. Upstream's MarshalJSON prefers
MultiSystem when non-empty, so the wire format is unchanged for requests
without cache_control. This refactor is a prerequisite for attaching
cache_control markers to system parts in the next commit.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add provider-specific usage details, fix streaming usage, and return
usage from all high-level APIs (Chat.Send, Generate[T], Agent.Run).
Breaking changes:
- Chat.Send/SendMessage/SendWithImages now return (string, *Usage, error)
- Generate[T]/GenerateWith[T] now return (T, *Usage, error)
- Agent.Run/RunMessages now return (string, *Usage, error)
New features:
- Usage.Details map for provider-specific token breakdowns
(reasoning, cached, audio, thoughts tokens)
- OpenAI streaming now captures usage via StreamOptions.IncludeUsage
- Google streaming now captures UsageMetadata from final chunk
- UsageTracker.Details() for accumulated detail totals
- ModelPricing and PricingRegistry for cost computation
Closes#2
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Add Audio struct alongside Image for sending audio attachments to
multimodal LLMs. OpenAI uses input_audio content parts (wav/mp3),
Google Gemini uses genai.NewPartFromBytes, and Anthropic skips
audio gracefully since it's not supported.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
v2 is a new Go module (v2/) with a dramatically simpler API:
- Unified Message type (no more Input marker interface)
- Define[T] for ergonomic tool creation with standard context.Context
- Chat session with automatic tool-call loop (agent loop)
- Streaming via pull-based StreamReader
- MCP one-call connect (MCPStdioServer, MCPHTTPServer, MCPSSEServer)
- Middleware support (logging, retry, timeout, usage tracking)
- Decoupled JSON Schema (map[string]any, no provider coupling)
- Sample tools: WebSearch, Browser, Exec, ReadFile, WriteFile, HTTP
- Providers: OpenAI, Anthropic, Google (all with streaming)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
