use rmcp::model::Tool;
use rmcp::ErrorData;
use serde_json::{json, Map, Value};
use crate::server::tool_trait::{get_str, McpTool, ToolContext, ToolOutput};
use crate::tool_defs::tool_def;
pub struct CtxPreloadTool;
impl McpTool for CtxPreloadTool {
fn name(&self) -> &'static str {
"ctx_preload"
}
fn tool_def(&self) -> Tool {
tool_def(
"ctx_preload",
"Proactive context loader — caches task-relevant files, returns L-curve-optimized summary (~50-100 tokens vs ~5000 for individual reads).",
json!({
"type": "object",
"properties": {
"task": {
"type": "string",
"description": "Task description (e.g. 'fix auth bug in validate_token')"
},
"path": {
"type": "string",
"description": "Project root (default: .)"
}
},
"required": ["task"]
}),
)
}
fn handle(
&self,
args: &Map<String, Value>,
ctx: &ToolContext,
) -> Result<ToolOutput, ErrorData> {
let task = get_str(args, "task").unwrap_or_default();
let resolved_path = if get_str(args, "path").is_some() {
ctx.resolved_path("path").map(String::from)
} else if let Some(ref session) = ctx.session {
let guard = tokio::task::block_in_place(|| session.blocking_read());
guard.project_root.clone()
} else {
None
};
let cache = ctx.cache.as_ref().unwrap();
let mut cache_guard = tokio::task::block_in_place(|| cache.blocking_write());
let mut result = crate::tools::ctx_preload::handle(
&mut cache_guard,
&task,
resolved_path.as_deref(),
ctx.crp_mode,
);
drop(cache_guard);
if let Some(ref session_lock) = ctx.session {
let mut session_guard = tokio::task::block_in_place(|| session_lock.blocking_write());
if session_guard.active_structured_intent.is_none()
|| session_guard
.active_structured_intent
.as_ref()
.is_none_or(|i| i.confidence < 0.6)
{
session_guard.set_task(&task, Some("preload"));
}
drop(session_guard);
let session_guard = tokio::task::block_in_place(|| session_lock.blocking_read());
if let Some(ref intent) = session_guard.active_structured_intent {
if let Some(ref ledger_lock) = ctx.ledger {
let ledger = tokio::task::block_in_place(|| ledger_lock.blocking_read());
if !ledger.entries.is_empty() {
let known: Vec<String> = session_guard
.files_touched
.iter()
.map(|f| f.path.clone())
.collect();
let deficit =
crate::core::context_deficit::detect_deficit(&ledger, intent, &known);
if !deficit.suggested_files.is_empty() {
result.push_str("\n\n--- SUGGESTED FILES ---");
for s in &deficit.suggested_files {
result.push_str(&format!(
"\n {} ({:?}, ~{} tok, mode: {})",
s.path, s.reason, s.estimated_tokens, s.recommended_mode
));
}
}
let pressure = ledger.pressure();
if pressure.utilization > 0.7 {
let plan = ledger.reinjection_plan(intent, 0.6);
if !plan.actions.is_empty() {
result.push_str("\n\n--- REINJECTION PLAN ---");
result.push_str(&format!(
"\n Context pressure: {:.0}% -> target: 60%",
pressure.utilization * 100.0
));
for a in &plan.actions {
result.push_str(&format!(
"\n {} : {} -> {} (frees ~{} tokens)",
a.path, a.current_mode, a.new_mode, a.tokens_freed
));
}
result.push_str(&format!(
"\n Total freeable: {} tokens",
plan.total_tokens_freed
));
}
}
}
}
}
}
Ok(ToolOutput {
text: result,
original_tokens: 0,
saved_tokens: 0,
mode: Some("preload".to_string()),
path: None,
changed: false,
})
}
}