multica/server/pkg/agent/agent.go
Jiayuan ffda18c809 feat(agent): add per-task session persistence for Claude Code resumption
Store the Claude Code session ID and working directory when a task
completes. On the next task for the same (agent, issue) pair, look up
the prior session and pass --resume <session_id> to Claude Code so
the agent retains conversation context across multiple tasks on the
same issue.

Changes:
- Migration 020: add session_id and work_dir columns to agent_task_queue
- CompleteAgentTask stores session_id and work_dir on completion
- GetLastTaskSession query retrieves prior session for (agent, issue)
- ClaimTaskByRuntime handler populates prior_session_id in response
- Daemon passes ResumeSessionID through to Claude backend Execute()
- Claude backend adds --resume flag when ResumeSessionID is set
2026-03-29 16:53:28 +08:00

100 lines
3.1 KiB
Go

// Package agent provides a unified interface for executing prompts via
// coding agents (Claude Code, Codex). It mirrors the happy-cli AgentBackend
// pattern, translated to idiomatic Go.
package agent
import (
"context"
"fmt"
"log/slog"
"time"
)
// Backend is the unified interface for executing prompts via coding agents.
type Backend interface {
// Execute runs a prompt and returns a Session for streaming results.
// The caller should read from Session.Messages (optional) and wait on
// Session.Result for the final outcome.
Execute(ctx context.Context, prompt string, opts ExecOptions) (*Session, error)
}
// ExecOptions configures a single execution.
type ExecOptions struct {
Cwd string
Model string
SystemPrompt string
MaxTurns int
Timeout time.Duration
ResumeSessionID string // if non-empty, resume a previous Claude Code session
}
// Session represents a running agent execution.
type Session struct {
// Messages streams events as the agent works. The channel is closed
// when the agent finishes (before Result is sent).
Messages <-chan Message
// Result receives exactly one value — the final outcome — then closes.
Result <-chan Result
}
// MessageType identifies the kind of Message.
type MessageType string
const (
MessageText MessageType = "text"
MessageToolUse MessageType = "tool-use"
MessageToolResult MessageType = "tool-result"
MessageStatus MessageType = "status"
MessageError MessageType = "error"
MessageLog MessageType = "log"
)
// Message is a unified event emitted by an agent during execution.
type Message struct {
Type MessageType
Content string // text content (Text, Error, Log)
Tool string // tool name (ToolUse, ToolResult)
CallID string // tool call ID (ToolUse, ToolResult)
Input map[string]any // tool input (ToolUse)
Output string // tool output (ToolResult)
Status string // agent status string (Status)
Level string // log level (Log)
}
// Result is the final outcome after an agent session completes.
type Result struct {
Status string // "completed", "failed", "aborted", "timeout"
Output string // accumulated text output
Error string // error message if failed
DurationMs int64
SessionID string
}
// Config configures a Backend instance.
type Config struct {
ExecutablePath string // path to CLI binary (claude or codex)
Env map[string]string // extra environment variables
Logger *slog.Logger
}
// New creates a Backend for the given agent type.
// Supported types: "claude", "codex".
func New(agentType string, cfg Config) (Backend, error) {
if cfg.Logger == nil {
cfg.Logger = slog.Default()
}
switch agentType {
case "claude":
return &claudeBackend{cfg: cfg}, nil
case "codex":
return &codexBackend{cfg: cfg}, nil
default:
return nil, fmt.Errorf("unknown agent type: %q (supported: claude, codex)", agentType)
}
}
// DetectVersion runs the agent CLI with --version and returns the output.
func DetectVersion(ctx context.Context, executablePath string) (string, error) {
return detectCLIVersion(ctx, executablePath)
}