1package agent
2
3import (
4 "context"
5 _ "embed"
6 "encoding/json"
7 "errors"
8 "fmt"
9 "net/http"
10 "os"
11 "time"
12
13 "charm.land/fantasy"
14
15 "github.com/charmbracelet/crush/internal/agent/prompt"
16 "github.com/charmbracelet/crush/internal/agent/tools"
17 "github.com/charmbracelet/crush/internal/permission"
18)
19
20//go:embed templates/fetch.md
21var fetchToolDescription []byte
22
23//go:embed templates/fetch_prompt.md.tpl
24var fetchPromptTmpl []byte
25
26func (c *coordinator) fetchTool(_ context.Context, client *http.Client) (fantasy.AgentTool, error) {
27 if client == nil {
28 client = &http.Client{
29 Timeout: 30 * time.Second,
30 Transport: &http.Transport{
31 MaxIdleConns: 100,
32 MaxIdleConnsPerHost: 10,
33 IdleConnTimeout: 90 * time.Second,
34 },
35 }
36 }
37
38 return fantasy.NewAgentTool(
39 tools.FetchToolName,
40 string(fetchToolDescription),
41 func(ctx context.Context, params tools.FetchParams, call fantasy.ToolCall) (fantasy.ToolResponse, error) {
42 if err := json.Unmarshal([]byte(call.Input), ¶ms); err != nil {
43 return fantasy.NewTextErrorResponse(fmt.Sprintf("error parsing parameters: %s", err)), nil
44 }
45
46 if params.URL == "" {
47 return fantasy.NewTextErrorResponse("url is required"), nil
48 }
49
50 if params.Prompt == "" {
51 return fantasy.NewTextErrorResponse("prompt is required"), nil
52 }
53
54 sessionID := tools.GetSessionFromContext(ctx)
55 if sessionID == "" {
56 return fantasy.ToolResponse{}, errors.New("session id missing from context")
57 }
58
59 agentMessageID := tools.GetMessageFromContext(ctx)
60 if agentMessageID == "" {
61 return fantasy.ToolResponse{}, errors.New("agent message id missing from context")
62 }
63
64 p := c.permissions.Request(
65 permission.CreatePermissionRequest{
66 SessionID: sessionID,
67 Path: c.cfg.WorkingDir(),
68 ToolCallID: call.ID,
69 ToolName: tools.FetchToolName,
70 Action: "fetch",
71 Description: fmt.Sprintf("Fetch and analyze content from URL: %s", params.URL),
72 Params: tools.FetchPermissionsParams(params),
73 },
74 )
75
76 if !p {
77 return fantasy.ToolResponse{}, permission.ErrorPermissionDenied
78 }
79
80 content, err := tools.FetchURLAndConvert(ctx, client, params.URL)
81 if err != nil {
82 return fantasy.NewTextErrorResponse(fmt.Sprintf("Failed to fetch URL: %s", err)), nil
83 }
84
85 tmpDir, err := os.MkdirTemp(c.cfg.Options.DataDirectory, "crush-fetch-*")
86 if err != nil {
87 return fantasy.NewTextErrorResponse(fmt.Sprintf("Failed to create temporary directory: %s", err)), nil
88 }
89 defer os.RemoveAll(tmpDir)
90
91 hasLargeContent := len(content) > tools.LargeContentThreshold
92 var fullPrompt string
93
94 if hasLargeContent {
95 tempFile, err := os.CreateTemp(tmpDir, "page-*.md")
96 if err != nil {
97 return fantasy.NewTextErrorResponse(fmt.Sprintf("Failed to create temporary file: %s", err)), nil
98 }
99 tempFilePath := tempFile.Name()
100
101 if _, err := tempFile.WriteString(content); err != nil {
102 tempFile.Close()
103 return fantasy.NewTextErrorResponse(fmt.Sprintf("Failed to write content to file: %s", err)), nil
104 }
105 tempFile.Close()
106
107 fullPrompt = fmt.Sprintf("%s\n\nThe web page from %s has been saved to: %s\n\nUse the view and grep tools to analyze this file and extract the requested information.", params.Prompt, params.URL, tempFilePath)
108 } else {
109 fullPrompt = fmt.Sprintf("%s\n\nWeb page URL: %s\n\n<webpage_content>\n%s\n</webpage_content>", params.Prompt, params.URL, content)
110 }
111
112 promptOpts := []prompt.Option{
113 prompt.WithWorkingDir(tmpDir),
114 }
115
116 promptTemplate, err := prompt.NewPrompt("fetch", string(fetchPromptTmpl), promptOpts...)
117 if err != nil {
118 return fantasy.ToolResponse{}, fmt.Errorf("error creating prompt: %s", err)
119 }
120
121 _, small, err := c.buildAgentModels(ctx)
122 if err != nil {
123 return fantasy.ToolResponse{}, fmt.Errorf("error building models: %s", err)
124 }
125
126 systemPrompt, err := promptTemplate.Build(ctx, small.Model.Provider(), small.Model.Model(), *c.cfg)
127 if err != nil {
128 return fantasy.ToolResponse{}, fmt.Errorf("error building system prompt: %s", err)
129 }
130
131 smallProviderCfg, ok := c.cfg.Providers.Get(small.ModelCfg.Provider)
132 if !ok {
133 return fantasy.ToolResponse{}, errors.New("small model provider not configured")
134 }
135
136 webFetchTool := tools.NewWebFetchTool(tmpDir, client)
137 fetchTools := []fantasy.AgentTool{
138 webFetchTool,
139 tools.NewGlobTool(tmpDir),
140 tools.NewGrepTool(tmpDir),
141 tools.NewViewTool(c.lspClients, c.permissions, tmpDir),
142 }
143
144 agent := NewSessionAgent(SessionAgentOptions{
145 LargeModel: small, // Use small model for both (fetch doesn't need large)
146 SmallModel: small,
147 SystemPromptPrefix: smallProviderCfg.SystemPromptPrefix,
148 SystemPrompt: systemPrompt,
149 DisableAutoSummarize: c.cfg.Options.DisableAutoSummarize,
150 IsYolo: c.permissions.SkipRequests(),
151 Sessions: c.sessions,
152 Messages: c.messages,
153 Tools: fetchTools,
154 })
155
156 agentToolSessionID := c.sessions.CreateAgentToolSessionID(agentMessageID, call.ID)
157 session, err := c.sessions.CreateTaskSession(ctx, agentToolSessionID, sessionID, "Fetch Analysis")
158 if err != nil {
159 return fantasy.ToolResponse{}, fmt.Errorf("error creating session: %s", err)
160 }
161
162 c.permissions.AutoApproveSession(session.ID)
163
164 // Use small model for web content analysis (faster and cheaper)
165 maxTokens := small.CatwalkCfg.DefaultMaxTokens
166 if small.ModelCfg.MaxTokens != 0 {
167 maxTokens = small.ModelCfg.MaxTokens
168 }
169
170 result, err := agent.Run(ctx, SessionAgentCall{
171 SessionID: session.ID,
172 Prompt: fullPrompt,
173 MaxOutputTokens: maxTokens,
174 ProviderOptions: getProviderOptions(small, smallProviderCfg),
175 Temperature: small.ModelCfg.Temperature,
176 TopP: small.ModelCfg.TopP,
177 TopK: small.ModelCfg.TopK,
178 FrequencyPenalty: small.ModelCfg.FrequencyPenalty,
179 PresencePenalty: small.ModelCfg.PresencePenalty,
180 })
181 if err != nil {
182 return fantasy.NewTextErrorResponse("error generating response"), nil
183 }
184
185 updatedSession, err := c.sessions.Get(ctx, session.ID)
186 if err != nil {
187 return fantasy.ToolResponse{}, fmt.Errorf("error getting session: %s", err)
188 }
189 parentSession, err := c.sessions.Get(ctx, sessionID)
190 if err != nil {
191 return fantasy.ToolResponse{}, fmt.Errorf("error getting parent session: %s", err)
192 }
193
194 parentSession.Cost += updatedSession.Cost
195
196 _, err = c.sessions.Save(ctx, parentSession)
197 if err != nil {
198 return fantasy.ToolResponse{}, fmt.Errorf("error saving parent session: %s", err)
199 }
200
201 return fantasy.NewTextResponse(result.Response.Content.Text()), nil
202 }), nil
203}