feat: add PicoLM local subprocess provider

pkg/config/config.go

@@ -263,6 +263,15 @@ type ProvidersConfig struct {
 	ShengSuanYun  ProviderConfig       `json:"shengsuanyun"`
 	DeepSeek      ProviderConfig       `json:"deepseek"`
 	GitHubCopilot ProviderConfig       `json:"github_copilot"`
+	PicoLM        PicoLMProviderConfig `json:"picolm"`
+}
+
+type PicoLMProviderConfig struct {
+	Binary    string `json:"binary" env:"PICOCLAW_PROVIDERS_PICOLM_BINARY"`
+	Model     string `json:"model" env:"PICOCLAW_PROVIDERS_PICOLM_MODEL"`
+	MaxTokens int    `json:"max_tokens" env:"PICOCLAW_PROVIDERS_PICOLM_MAX_TOKENS"`
+	Threads   int    `json:"threads" env:"PICOCLAW_PROVIDERS_PICOLM_THREADS"`
+	Template  string `json:"template" env:"PICOCLAW_PROVIDERS_PICOLM_TEMPLATE"`
 }
 
 type ProviderConfig struct {

pkg/providers/factory.go

@@ -22,6 +22,7 @@ const (
 	providerTypeClaudeCLI
 	providerTypeCodexCLI
 	providerTypeGitHubCopilot
+	providerTypePicoLM
 )
 
 type providerSelection struct {
@@ -187,6 +188,11 @@ func resolveProviderSelection(cfg *config.Config) (providerSelection, error) {
 			sel.providerType = providerTypeCodexCLI
 			sel.workspace = workspace
 			return sel, nil
+		case "picolm":
+			if cfg.Providers.PicoLM.Binary != "" || cfg.Providers.PicoLM.Model != "" {
+				sel.providerType = providerTypePicoLM
+				return sel, nil
+			}
 		case "deepseek":
 			if cfg.Providers.DeepSeek.APIKey != "" {
 				sel.apiKey = cfg.Providers.DeepSeek.APIKey
@@ -354,6 +360,8 @@ func CreateProvider(cfg *config.Config) (LLMProvider, error) {
 		return NewCodexCliProvider(sel.workspace), nil
 	case providerTypeGitHubCopilot:
 		return NewGitHubCopilotProvider(sel.apiBase, sel.connectMode, sel.model)
+	case providerTypePicoLM:
+		return NewPicoLMProvider(cfg.Providers.PicoLM), nil
 	default:
 		return NewHTTPProvider(sel.apiKey, sel.apiBase, sel.proxy), nil
 	}

pkg/providers/picolm_provider.go

@@ -0,0 +1,168 @@
+package providers
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/sipeed/picoclaw/pkg/config"
+)
+
+// PicoLMProvider implements LLMProvider by spawning the picolm binary as a subprocess.
+type PicoLMProvider struct {
+	binary    string
+	model     string
+	maxTokens int
+	threads   int
+	template  string
+}
+
+// NewPicoLMProvider creates a new PicoLM provider from config.
+func NewPicoLMProvider(cfg config.PicoLMProviderConfig) *PicoLMProvider {
+	binary := expandHome(cfg.Binary)
+	model := expandHome(cfg.Model)
+	maxTokens := cfg.MaxTokens
+	if maxTokens <= 0 {
+		maxTokens = 256
+	}
+	threads := cfg.Threads
+	if threads <= 0 {
+		threads = 4
+	}
+	template := cfg.Template
+	if template == "" {
+		template = "chatml"
+	}
+	return &PicoLMProvider{
+		binary:    binary,
+		model:     model,
+		maxTokens: maxTokens,
+		threads:   threads,
+		template:  template,
+	}
+}
+
+// Chat implements LLMProvider.Chat by executing the picolm binary.
+func (p *PicoLMProvider) Chat(ctx context.Context, messages []Message, tools []ToolDefinition, model string, options map[string]interface{}) (*LLMResponse, error) {
+	if p.binary == "" {
+		return nil, fmt.Errorf("picolm binary path not configured")
+	}
+	if p.model == "" {
+		return nil, fmt.Errorf("picolm model path not configured")
+	}
+
+	prompt := p.buildPrompt(messages, tools)
+
+	args := []string{
+		p.model,
+		"-n", fmt.Sprintf("%d", p.maxTokens),
+		"-j", fmt.Sprintf("%d", p.threads),
+		"-t", "0.7",
+	}
+
+	if len(tools) > 0 {
+		args = append(args, "--json")
+	}
+
+	cmd := exec.CommandContext(ctx, p.binary, args...)
+	cmd.Stdin = bytes.NewReader([]byte(prompt))
+	var stdout, stderr bytes.Buffer
+	cmd.Stdout = &stdout
+	cmd.Stderr = &stderr
+
+	err := cmd.Run()
+
+	// Try to parse stdout even on non-zero exit, as picolm may print diagnostics to stderr.
+	if output := strings.TrimSpace(stdout.String()); output != "" {
+		toolCalls := extractToolCallsFromText(output)
+		finishReason := "stop"
+		content := output
+		if len(toolCalls) > 0 {
+			finishReason = "tool_calls"
+			content = stripToolCallsFromText(output)
+		}
+		return &LLMResponse{
+			Content:      strings.TrimSpace(content),
+			ToolCalls:    toolCalls,
+			FinishReason: finishReason,
+		}, nil
+	}
+
+	if err != nil {
+		if ctx.Err() == context.Canceled {
+			return nil, ctx.Err()
+		}
+		if stderrStr := stderr.String(); stderrStr != "" {
+			return nil, fmt.Errorf("picolm error: %s", stderrStr)
+		}
+		return nil, fmt.Errorf("picolm error: %w", err)
+	}
+
+	return &LLMResponse{
+		Content:      "",
+		FinishReason: "stop",
+	}, nil
+}
+
+// GetDefaultModel returns the default model identifier.
+func (p *PicoLMProvider) GetDefaultModel() string {
+	return "picolm-local"
+}
+
+// buildPrompt formats messages into a ChatML template for picolm.
+func (p *PicoLMProvider) buildPrompt(messages []Message, tools []ToolDefinition) string {
+	var sb strings.Builder
+
+	var systemParts []string
+	for _, msg := range messages {
+		if msg.Role == "system" {
+			systemParts = append(systemParts, msg.Content)
+		}
+	}
+
+	if len(systemParts) > 0 {
+		sb.WriteString("<|system|>\n")
+		sb.WriteString(strings.Join(systemParts, "\n\n"))
+		sb.WriteString("</s>\n")
+	}
+
+	for _, msg := range messages {
+		switch msg.Role {
+		case "user":
+			sb.WriteString("<|user|>\n")
+			sb.WriteString(msg.Content)
+			sb.WriteString("</s>\n")
+		case "assistant":
+			sb.WriteString("<|assistant|>\n")
+			sb.WriteString(msg.Content)
+			sb.WriteString("</s>\n")
+		case "tool":
+			sb.WriteString("<|user|>\n")
+			sb.WriteString(fmt.Sprintf("[Tool Result for %s]: %s", msg.ToolCallID, msg.Content))
+			sb.WriteString("</s>\n")
+		}
+	}
+
+	// Open assistant turn for the model to complete
+	sb.WriteString("<|assistant|>\n")
+
+	return sb.String()
+}
+
+// expandHome expands ~ to the user's home directory.
+func expandHome(path string) string {
+	if path == "" {
+		return path
+	}
+	if path[0] == '~' {
+		home, _ := os.UserHomeDir()
+		if len(path) > 1 && path[1] == '/' {
+			return home + path[1:]
+		}
+		return home
+	}
+	return path
+}