use rmcp::ErrorData;
use rmcp::model::Tool;
use serde_json::{Map, Value, json};
use crate::server::tool_trait::{McpTool, ToolContext, ToolOutput, get_str};
use crate::tool_defs::tool_def;
pub struct CtxOverviewTool;
impl McpTool for CtxOverviewTool {
fn name(&self) -> &'static str {
"ctx_overview"
}
fn tool_def(&self) -> Tool {
tool_def(
"ctx_overview",
"WORKFLOW: call at session START before ctx_compose/ctx_read.\n\
ANTIPATTERN: NOT for source code — structure only. Use ctx_compose for code understanding.\n\
Project map — task='your goal' scopes files by relevance (PageRank on symbol graph).\n\
High-level structure only, no source body. ~10x cheaper than ctx_compose.",
json!({
"type": "object",
"properties": {
"task": {
"type": "string",
"description": "Short English task for relevance scoring"
},
"path": {
"type": "string",
"description": "Project root"
}
}
}),
)
}
fn handle(
&self,
args: &Map<String, Value>,
ctx: &ToolContext,
) -> Result<ToolOutput, ErrorData> {
let task = get_str(args, "task");
let resolved_path = if get_str(args, "path").is_some() {
if let Some(p) = ctx.resolved_path("path") {
Some(p.to_string())
} else if let Some(err) = ctx.path_error("path") {
return Err(ErrorData::invalid_params(format!("path: {err}"), None));
} else {
None
}
} else if let Some(ref session) = ctx.session {
let guard = crate::server::bounded_lock::read(session, "ctx_overview:session");
guard.as_ref().and_then(|g| g.project_root.clone())
} else {
None
};
let cache = ctx
.cache
.as_ref()
.ok_or_else(|| ErrorData::internal_error("cache not available", None))?;
let Some(guard) = crate::server::bounded_lock::read(cache, "ctx_overview:cache") else {
return Ok(ToolOutput::simple(
"[overview temporarily unavailable — cache busy]".to_string(),
));
};
let (result, _complete) = crate::tools::ctx_overview::handle(
&guard,
task.as_deref(),
resolved_path.as_deref(),
ctx.crp_mode,
);
Ok(ToolOutput {
text: result,
original_tokens: 0,
saved_tokens: 0,
mode: Some("overview".to_string()),
path: None,
changed: false,
shell_outcome: None,
content_blocks: None,
})
}
}