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lean_ctx/tools/registered/
ctx_shell.rs

1use rmcp::model::Tool;
2use rmcp::ErrorData;
3use serde_json::{json, Map, Value};
4
5use crate::server::tool_trait::{get_bool, get_str, McpTool, ToolContext, ToolOutput};
6use crate::tool_defs::tool_def;
7
8pub struct CtxShellTool;
9
10impl McpTool for CtxShellTool {
11    fn name(&self) -> &'static str {
12        "ctx_shell"
13    }
14
15    fn tool_def(&self) -> Tool {
16        tool_def(
17            "ctx_shell",
18            "Run shell command (compressed output, 95+ patterns). Use raw=true to skip compression. cwd sets working directory (persists across calls via cd tracking). Output redaction is on by default for non-admin roles (admin can disable).",
19            json!({
20                "type": "object",
21                "properties": {
22                    "command": { "type": "string", "description": "Shell command to execute" },
23                    "raw": { "type": "boolean", "description": "Skip compression, return full uncompressed output. Redaction still applies by default for non-admin roles." },
24                    "cwd": { "type": "string", "description": "Working directory for the command. If omitted, uses last cd target or project root." },
25                    "env": { "type": "object", "description": "Additional environment variables to set for the command. Use to pass agent runtime vars (e.g. CODEX_THREAD_ID).", "additionalProperties": { "type": "string" } }
26                },
27                "required": ["command"]
28            }),
29        )
30    }
31
32    fn handle(
33        &self,
34        args: &Map<String, Value>,
35        ctx: &ToolContext,
36    ) -> Result<ToolOutput, ErrorData> {
37        let command = get_str(args, "command")
38            .ok_or_else(|| ErrorData::invalid_params("command is required", None))?;
39
40        if let Some(rejection) = crate::tools::ctx_shell::validate_command(&command) {
41            return Ok(ToolOutput::simple(rejection));
42        }
43
44        if let Err(msg) = crate::core::shell_allowlist::check_shell_allowlist(&command) {
45            return Ok(ToolOutput::simple(msg));
46        }
47
48        tokio::task::block_in_place(|| {
49            let session_lock = ctx
50                .session
51                .as_ref()
52                .ok_or_else(|| ErrorData::internal_error("session not available", None))?;
53
54            let explicit_cwd = get_str(args, "cwd");
55            let effective_cwd = {
56                let session = session_lock.blocking_read();
57                session.effective_cwd(explicit_cwd.as_deref())
58            };
59
60            {
61                let mut session = session_lock.blocking_write();
62                session.update_shell_cwd(&command);
63                let root_missing = session
64                    .project_root
65                    .as_deref()
66                    .is_none_or(|r| r.trim().is_empty());
67                if root_missing {
68                    let home = dirs::home_dir().map(|h| h.to_string_lossy().to_string());
69                    if let Some(root) = crate::core::protocol::detect_project_root(&effective_cwd) {
70                        if home.as_deref() != Some(root.as_str()) {
71                            session.project_root = Some(root.clone());
72                            crate::core::index_orchestrator::ensure_all_background(&root);
73                        }
74                    }
75                }
76            }
77
78            let arg_raw = get_bool(args, "raw").unwrap_or(false);
79            let arg_bypass = get_bool(args, "bypass").unwrap_or(false);
80            let env_disabled = std::env::var("LEAN_CTX_DISABLED").is_ok();
81            let env_raw = std::env::var("LEAN_CTX_RAW").is_ok();
82            let (raw, bypass) = resolve_shell_raw_flags(arg_raw, arg_bypass, env_disabled, env_raw);
83
84            let crp_mode = ctx.crp_mode;
85            let cmd_clone = command.clone();
86            let cwd_clone = effective_cwd;
87
88            let extra_env: std::collections::HashMap<String, String> = args
89                .get("env")
90                .and_then(|v| v.as_object())
91                .map(|obj| {
92                    obj.iter()
93                        .filter_map(|(k, v)| v.as_str().map(|s| (k.clone(), s.to_string())))
94                        .collect()
95                })
96                .unwrap_or_default();
97
98            let (output, _exit_code) = crate::server::execute::execute_command_with_env(
99                &cmd_clone, &cwd_clone, &extra_env,
100            );
101
102            let (result_out, original, saved, tee_hint) = if raw {
103                let tokens = crate::core::tokens::count_tokens(&output);
104                (output, tokens, 0, String::new())
105            } else {
106                let result = crate::tools::ctx_shell::handle(&cmd_clone, &output, crp_mode);
107                let original = crate::core::tokens::count_tokens(&output);
108                let sent = crate::core::tokens::count_tokens(&result);
109                let saved = original.saturating_sub(sent);
110
111                let cfg = crate::core::config::Config::load();
112                let tee_hint = match cfg.tee_mode {
113                    crate::core::config::TeeMode::Always => {
114                        crate::shell::save_tee(&cmd_clone, &output)
115                            .map(|p| format!("\n[full output: {p}]"))
116                            .unwrap_or_default()
117                    }
118                    crate::core::config::TeeMode::Failures
119                        if !output.trim().is_empty()
120                            && (output.contains("error")
121                                || output.contains("Error")
122                                || output.contains("ERROR")) =>
123                    {
124                        crate::shell::save_tee(&cmd_clone, &output)
125                            .map(|p| format!("\n[full output: {p}]"))
126                            .unwrap_or_default()
127                    }
128                    _ => String::new(),
129                };
130
131                (result, original, saved, tee_hint)
132            };
133
134            let mode = if bypass {
135                Some("bypass".to_string())
136            } else if raw {
137                Some("raw".to_string())
138            } else {
139                None
140            };
141
142            let shell_mismatch = if cfg!(windows) && !raw {
143                shell_mismatch_hint(&command, &result_out)
144            } else {
145                String::new()
146            };
147
148            let result_out = crate::core::redaction::redact_text_if_enabled(&result_out);
149            let final_out = format!("{result_out}{tee_hint}{shell_mismatch}");
150
151            Ok(ToolOutput {
152                text: final_out,
153                original_tokens: original,
154                saved_tokens: saved,
155                mode,
156                path: None,
157                changed: false,
158            })
159        })
160    }
161}
162
163#[allow(clippy::fn_params_excessive_bools)]
164fn resolve_shell_raw_flags(
165    arg_raw: bool,
166    arg_bypass: bool,
167    env_disabled: bool,
168    env_raw: bool,
169) -> (bool, bool) {
170    let bypass = arg_bypass || env_raw;
171    let raw = arg_raw || bypass || env_disabled;
172    (raw, bypass)
173}
174
175fn shell_mismatch_hint(command: &str, output: &str) -> String {
176    let shell = crate::shell::shell_name();
177    let is_posix = matches!(shell.as_str(), "bash" | "sh" | "zsh" | "fish");
178    let has_error = output.contains("is not recognized")
179        || output.contains("not found")
180        || output.contains("command not found");
181
182    if !has_error {
183        return String::new();
184    }
185
186    let powershell_cmds = [
187        "Get-Content",
188        "Select-Object",
189        "Get-ChildItem",
190        "Set-Location",
191        "Where-Object",
192        "ForEach-Object",
193        "Select-String",
194        "Invoke-Expression",
195        "Write-Output",
196    ];
197    let uses_powershell = powershell_cmds
198        .iter()
199        .any(|c| command.contains(c) || command.contains(&c.to_lowercase()));
200
201    if is_posix && uses_powershell {
202        format!(
203            "\n[shell: {shell} — use POSIX commands (cat, head, grep, find, ls) not PowerShell cmdlets]"
204        )
205    } else {
206        String::new()
207    }
208}