lean_ctx_server/tools/registered/
ctx_tools.rs

1// SPDX-License-Identifier: Apache-2.0
2use rmcp::ErrorData;
3use rmcp::model::Tool;
4use serde_json::{Map, Value, json};
5
6use crate::server::tool_trait::{McpTool, ToolContext, ToolOutput};
7use lean_ctx::tool_defs::tool_def;
8
9/// `ctx_tools` — MCP Tool-Catalog Gateway (#210). Aggregates downstream MCP
10/// servers and returns a per-query top-N shortlist instead of injecting every
11/// downstream schema, then proxies the real call.
12pub struct CtxToolsTool;
13
14impl McpTool for CtxToolsTool {
15    fn name(&self) -> &'static str {
16        "ctx_tools"
17    }
18
19    fn tool_def(&self) -> Tool {
20        tool_def(
21            "ctx_tools",
22            "Gateway to downstream MCP servers — unlimited external tools at ~constant context cost.\n\
23             actions: find (query → top-N relevant tools) | call (proxy a server::tool) |\n\
24             list (servers+counts) | refresh.\n\
25             WORKFLOW: find to discover, then call the chosen server::tool.\n\
26             ANTIPATTERN: not for built-in tools — use those directly.",
27            json!({
28                "type": "object",
29                "properties": {
30                    "action": {
31                        "type": "string",
32                        "enum": ["find", "call", "list", "refresh"],
33                        "description": "find|call|list|refresh"
34                    },
35                    "query": { "type": "string", "description": "What you want to do (for find)" },
36                    "tool": { "type": "string", "description": "`server::tool` handle (for call)" },
37                    "arguments": { "type": "object", "description": "Arguments for downstream tool (call)" }
38                },
39                "allOf": [
40                    {
41                        "if": { "properties": { "action": { "const": "call" } }, "required": ["action"] },
42                        "then": { "required": ["action", "tool"] }
43                    }
44                ]
45            }),
46        )
47    }
48
49    fn handle(
50        &self,
51        args: &Map<String, Value>,
52        ctx: &ToolContext,
53    ) -> Result<ToolOutput, ErrorData> {
54        // `project_root` is threaded through so the gateway's L3 consolidation
55        // (#1095) can write addon output into the project's BM25/graph/knowledge
56        // stores. Empty (one-shot CLI ctx) disables project-scoped indexing.
57        match crate::tools::ctx_tools::run(args, &ctx.project_root) {
58            Ok(text) => Ok(ToolOutput::simple(text)),
59            Err(e) => Err(ErrorData::invalid_params(e, None)),
60        }
61    }
62}
lean_ctx_server/tools/registered/ctx_tools.rs

lean_ctx_server/tools/registered/
ctx_tools.rs
