Method runAgentLoop

cmd/wasm/runtime_wasm.go:251–378

runAgentLoop runs the full agentic loop: stream completions, process tool calls, handle handoffs, and loop until the model says stop or we hit maxIterations.

(ctx context.Context, agentName string, messages []chat.Message)

// calls, handle handoffs, and loop until the model says stop or we hit
// maxIterations.
func (rt *wasmRuntime) runAgentLoop(ctx context.Context, agentName string, messages []chat.Message) (map[string]any, error) {
	if agentName == "" {
		agentName = rt.cfg.Agents[0].Name
	}
	rt.currentAgent = agentName

	a, ok := rt.agents[rt.currentAgent]
	if !ok {
		return nil, fmt.Errorf("agent %q not found", rt.currentAgent)
	}

	// Prepend system instruction.
	if a.Instruction() != "" && (len(messages) == 0 || messages[0].Role != chat.MessageRoleSystem) {
		sys := chat.Message{Role: chat.MessageRoleSystem, Content: a.Instruction()}
		messages = append([]chat.Message{sys}, messages...)
	}

	// Fire session_start hook.
	rt.fireHook(ctx, rt.currentAgent, hooks.EventSessionStart, &hooks.Input{})

	var totalUsage chat.Usage
	iteration := 0

	for iteration < maxIterations {
		iteration++

		if ctx.Err() != nil {
			return nil, ctx.Err()
		}

		a = rt.agents[rt.currentAgent]

		// Fire turn_start hook.
		turnCtx := rt.fireHook(ctx, rt.currentAgent, hooks.EventTurnStart, &hooks.Input{})
		if turnCtx != nil && turnCtx.AdditionalContext != "" {
			// Inject context as a transient system message.
			ctxMsg := chat.Message{Role: chat.MessageRoleSystem, Content: turnCtx.AdditionalContext}
			messages = append(messages, ctxMsg)
		}

		// Get tools for this agent.
		agentTools, err := a.Tools(ctx)
		if err != nil {
			slog.WarnContext(ctx, "Failed to get tools", "agent", rt.currentAgent, "error", err)
			agentTools = nil
		}

		// Add delegation tools if agent has handoffs or sub-agents.
		agentTools = rt.addDelegationTools(a, agentTools)

		// Try primary model with fallback chain.
		streamResult, err := rt.streamWithFallback(ctx, a, messages, agentTools)
		if err != nil {
			return nil, fmt.Errorf("model call failed: %w", err)
		}

		// Accumulate usage.
		if streamResult.usage != nil {