LLMs occasionally return numeric or boolean tool-call fields as JSON
strings (e.g. "3" instead of 3, "true" instead of true), which Go's
strict json.Unmarshal rejects. The strict unmarshal stays as the happy
path; on failure we retry with a coercion pass that walks the target
struct (recursing into nested structs, slices, maps, and pointer fields)
and converts strings to the appropriate kind. Returns the original error
if coercion can't recover.
Co-Authored-By: Claude Opus 4.7 <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>
steve