lean_ctx/tools/registered/
ctx_fill.rs1use rmcp::model::Tool;
2use rmcp::ErrorData;
3use serde_json::{json, Map, Value};
4
5use crate::server::tool_trait::{
6 get_str, get_str_array, get_usize, McpTool, ToolContext, ToolOutput,
7};
8use crate::tool_defs::tool_def;
9
10pub struct CtxFillTool;
11
12impl McpTool for CtxFillTool {
13 fn name(&self) -> &'static str {
14 "ctx_fill"
15 }
16
17 fn tool_def(&self) -> Tool {
18 tool_def(
19 "ctx_fill",
20 "Budget-aware context fill — auto-selects compression per file within token limit.",
21 json!({
22 "type": "object",
23 "properties": {
24 "paths": {
25 "type": "array",
26 "items": { "type": "string" },
27 "description": "File paths to consider"
28 },
29 "budget": {
30 "type": "integer",
31 "description": "Maximum token budget to fill"
32 },
33 "task": {
34 "type": "string",
35 "description": "Optional task (short English preferred) for intent-driven pruning"
36 }
37 },
38 "required": ["paths", "budget"]
39 }),
40 )
41 }
42
43 fn handle(
44 &self,
45 args: &Map<String, Value>,
46 ctx: &ToolContext,
47 ) -> Result<ToolOutput, ErrorData> {
48 let raw_paths = get_str_array(args, "paths")
49 .ok_or_else(|| ErrorData::invalid_params("paths array is required", None))?;
50 let budget = get_usize(args, "budget")
51 .ok_or_else(|| ErrorData::invalid_params("budget is required (non-negative)", None))?;
52 let task = get_str(args, "task");
53
54 tokio::task::block_in_place(|| {
55 let session_lock = ctx
56 .session
57 .as_ref()
58 .ok_or_else(|| ErrorData::internal_error("session not available", None))?;
59 let cache_lock = ctx
60 .cache
61 .as_ref()
62 .ok_or_else(|| ErrorData::internal_error("cache not available", None))?;
63
64 let mut paths = Vec::with_capacity(raw_paths.len());
65 {
66 let session = session_lock.blocking_read();
67 for p in &raw_paths {
68 match super::resolve_path_sync(&session, p) {
69 Ok(resolved) => paths.push(resolved),
70 Err(e) => {
71 return Err(ErrorData::invalid_params(e, None));
72 }
73 }
74 }
75 }
76
77 let timeout_dur =
78 crate::core::io_health::adaptive_timeout(std::time::Duration::from_secs(10));
79 let Ok(mut cache) = tokio::runtime::Handle::current()
80 .block_on(tokio::time::timeout(timeout_dur, cache_lock.write()))
81 else {
82 crate::core::io_health::record_freeze();
83 return Err(ErrorData::internal_error(
84 "cache busy (ctx_fill) — retry in a moment",
85 None,
86 ));
87 };
88 let output = crate::tools::ctx_fill::handle(
89 &mut cache,
90 &paths,
91 budget,
92 ctx.crp_mode,
93 task.as_deref(),
94 );
95 drop(cache);
96
97 Ok(ToolOutput {
98 text: output,
99 original_tokens: 0,
100 saved_tokens: 0,
101 mode: Some(format!("budget:{budget}")),
102 path: None,
103 changed: false,
104 shell_outcome: None,
105 })
106 })
107 }
108}