Run/RunStream took the new turn as a bare string, which had nowhere
to carry ContentPart attachments. Both now take an llm.Message
(Role is forced to RoleUser regardless of what the caller sets), so a
caller building a multimodal turn just fills in Content/Parts on it
instead of the loop needing a second, parallel parameter.
subagent.go and every test call site are updated to wrap their string
prompt as llm.Message{Role: llm.RoleUser, Content: ...} — SubAgent.Run
itself is untouched, it still takes a plain task string.
|
||
|---|---|---|
| .. | ||
| integration_test.go | ||
| loop.go | ||
| loop_test.go | ||
| README.es.md | ||
| README.md | ||
| subagent.go | ||
| subagent_test.go | ||
| thinking_budget_test.go | ||
| unparsed_toolcall_test.go | ||
pkg/agent
The main loop that runs an LLM agent with guardrails.
Responsibility
Coordinate the iterative cycle between the LLM and tool execution:
while iteration < MaxIterations:
response = llm.Generate(messages, tools)
if no tool calls: return response
for tool_call in response.ToolCalls:
if needs_approval: ask_user()
result = execute(tool_call)
append tool result to messages
Public API
type Loop interface {
Run(ctx context.Context, input string, history ...llm.Message) (Response, error)
RunStream(ctx context.Context, input string, history ...llm.Message) iter.Seq2[Chunk, error]
}
type Config struct {
LLM llm.LLMClient
Persona persona.Persona
Tools tools.Registry
Sandbox Sandbox
MaxIters int
Approver Approver // nil = auto-approve all
OnIteration func(Iteration) // observability hook
}
type Response struct {
Content string
ToolCalls []tools.Call
Iterations int
Duration time.Duration
TokenUsage llm.TokenUsage
}
Guarantees
- Termination: Always terminates (max iterations, error, or final response)
- Idempotency: Re-running with the same input produces the same output (given the same LLM)
- Observability: Each iteration emits an OpenTelemetry span
- Approval: Destructive tools (
Askpermission) require confirmation
See also
- pkg/tools — Tool execution
- pkg/llm — LLMClient interface
- pkg/persona — Persona assembly