ZIm/crates/agent/src/context_server_tool.rs
Bennet Bo Fenner 95d78ff8d5
context server: Make requests type safe (#32254)
This changes the context server crate so that the input/output for a
request are encoded at the type level, similar to how it is done for LSP
requests.

This also makes it easier to write tests that mock context servers, e.g.
you can write something like this now when using the `test-support`
feature of the `context-server` crate:

```rust
create_fake_transport("mcp-1", cx.background_executor())
    .on_request::<context_server::types::request::PromptsList>(|_params| {
        PromptsListResponse {
            prompts: vec![/* some prompts */],
            ..
        }
    })
```

Release Notes:

- N/A
2025-06-06 17:47:21 +02:00

138 lines
4.3 KiB
Rust

use std::sync::Arc;
use anyhow::{Result, anyhow, bail};
use assistant_tool::{ActionLog, Tool, ToolResult, ToolSource};
use context_server::{ContextServerId, types};
use gpui::{AnyWindowHandle, App, Entity, Task};
use language_model::{LanguageModel, LanguageModelRequest, LanguageModelToolSchemaFormat};
use project::{Project, context_server_store::ContextServerStore};
use ui::IconName;
pub struct ContextServerTool {
store: Entity<ContextServerStore>,
server_id: ContextServerId,
tool: types::Tool,
}
impl ContextServerTool {
pub fn new(
store: Entity<ContextServerStore>,
server_id: ContextServerId,
tool: types::Tool,
) -> Self {
Self {
store,
server_id,
tool,
}
}
}
impl Tool for ContextServerTool {
fn name(&self) -> String {
self.tool.name.clone()
}
fn description(&self) -> String {
self.tool.description.clone().unwrap_or_default()
}
fn icon(&self) -> IconName {
IconName::Cog
}
fn source(&self) -> ToolSource {
ToolSource::ContextServer {
id: self.server_id.clone().0.into(),
}
}
fn needs_confirmation(&self, _: &serde_json::Value, _: &App) -> bool {
true
}
fn may_perform_edits(&self) -> bool {
true
}
fn input_schema(&self, format: LanguageModelToolSchemaFormat) -> Result<serde_json::Value> {
let mut schema = self.tool.input_schema.clone();
assistant_tool::adapt_schema_to_format(&mut schema, format)?;
Ok(match schema {
serde_json::Value::Null => {
serde_json::json!({ "type": "object", "properties": [] })
}
serde_json::Value::Object(map) if map.is_empty() => {
serde_json::json!({ "type": "object", "properties": [] })
}
_ => schema,
})
}
fn ui_text(&self, _input: &serde_json::Value) -> String {
format!("Run MCP tool `{}`", self.tool.name)
}
fn run(
self: Arc<Self>,
input: serde_json::Value,
_request: Arc<LanguageModelRequest>,
_project: Entity<Project>,
_action_log: Entity<ActionLog>,
_model: Arc<dyn LanguageModel>,
_window: Option<AnyWindowHandle>,
cx: &mut App,
) -> ToolResult {
if let Some(server) = self.store.read(cx).get_running_server(&self.server_id) {
let tool_name = self.tool.name.clone();
let server_clone = server.clone();
let input_clone = input.clone();
cx.spawn(async move |_cx| {
let Some(protocol) = server_clone.client() else {
bail!("Context server not initialized");
};
let arguments = if let serde_json::Value::Object(map) = input_clone {
Some(map.into_iter().collect())
} else {
None
};
log::trace!(
"Running tool: {} with arguments: {:?}",
tool_name,
arguments
);
let response = protocol
.request::<context_server::types::request::CallTool>(
context_server::types::CallToolParams {
name: tool_name,
arguments,
meta: None,
},
)
.await?;
let mut result = String::new();
for content in response.content {
match content {
types::ToolResponseContent::Text { text } => {
result.push_str(&text);
}
types::ToolResponseContent::Image { .. } => {
log::warn!("Ignoring image content from tool response");
}
types::ToolResponseContent::Resource { .. } => {
log::warn!("Ignoring resource content from tool response");
}
}
}
Ok(result.into())
})
.into()
} else {
Task::ready(Err(anyhow!("Context server not found"))).into()
}
}
}