lean_ctx/tools/registered/
ctx_metrics.rs

1use rmcp::model::Tool;
2use rmcp::ErrorData;
3use serde_json::{json, Map, Value};
4
5use crate::server::tool_trait::{McpTool, ToolContext, ToolOutput};
6use crate::tool_defs::tool_def;
7
8pub struct CtxMetricsTool;
9
10impl McpTool for CtxMetricsTool {
11    fn name(&self) -> &'static str {
12        "ctx_metrics"
13    }
14
15    fn tool_def(&self) -> Tool {
16        tool_def(
17            "ctx_metrics",
18            "Session token stats, cache rates, per-tool savings.",
19            json!({
20                "type": "object",
21                "properties": {}
22            }),
23        )
24    }
25
26    fn handle(
27        &self,
28        _args: &Map<String, Value>,
29        ctx: &ToolContext,
30    ) -> Result<ToolOutput, ErrorData> {
31        let cache = ctx
32            .cache
33            .as_ref()
34            .ok_or_else(|| ErrorData::internal_error("cache not available", None))?;
35        let Some(cache_guard) = crate::server::bounded_lock::read(cache, "ctx_metrics:cache")
36        else {
37            return Ok(ToolOutput::simple(
38                "[metrics unavailable — cache busy, retry]".to_string(),
39            ));
40        };
41        let calls = ctx
42            .tool_calls
43            .as_ref()
44            .ok_or_else(|| ErrorData::internal_error("tool_calls not available", None))?;
45        let Some(calls_guard) = crate::server::bounded_lock::read(calls, "ctx_metrics:calls")
46        else {
47            return Ok(ToolOutput::simple(
48                "[metrics unavailable — calls lock busy, retry]".to_string(),
49            ));
50        };
51        let mut result =
52            crate::tools::ctx_metrics::handle(&cache_guard, &calls_guard, ctx.crp_mode);
53        drop(cache_guard);
54        drop(calls_guard);
55
56        if let Some(ref ps) = ctx.pipeline_stats {
57            let Some(stats) = crate::server::bounded_lock::read(ps, "ctx_metrics:pipeline") else {
58                return Ok(ToolOutput::simple(result));
59            };
60            if stats.runs > 0 {
61                result.push_str("\n\n--- PIPELINE METRICS ---\n");
62                result.push_str(&stats.format_summary());
63            }
64        }
65
66        let (ts_hits, regex_hits) = crate::core::signatures::signature_backend_stats();
67        if ts_hits + regex_hits > 0 {
68            result.push_str("\n--- SIGNATURE BACKEND ---\n");
69            result.push_str(&format!(
70                "tree-sitter: {} | regex fallback: {} | ratio: {:.0}%\n",
71                ts_hits,
72                regex_hits,
73                if ts_hits + regex_hits > 0 {
74                    ts_hits as f64 / (ts_hits + regex_hits) as f64 * 100.0
75                } else {
76                    0.0
77                }
78            ));
79        }
80
81        Ok(ToolOutput::simple(result))
82    }
83}
lean_ctx/tools/registered/ctx_metrics.rs

lean_ctx/tools/registered/
ctx_metrics.rs
