aether_cli/
runtime.rs

1use crate::error::CliError;
2use aether_core::agent_spec::{AgentSpec, McpConfigSource};
3use aether_core::core::{AgentBuilder, AgentDeps, AgentHandle, Prompt};
4use aether_core::events::{AgentEvent, Command};
5use aether_core::mcp::McpBuilder;
6use aether_core::mcp::McpSpawnResult;
7use aether_core::mcp::mcp;
8use aether_core::mcp::run_mcp_task::McpCommand;
9use llm::{ChatMessage, LlmModel, ToolDefinition};
10use mcp_servers::McpBuilderExt;
11use mcp_utils::client::{McpClientEvent, McpConnectionDetails, McpServer, OAuthHandlerFactory};
12use std::path::{Path, PathBuf};
13use tokio::sync::mpsc::{Receiver, Sender};
14use tokio::task::JoinHandle;
15use tracing::debug;
16
17pub struct RuntimeBuilder {
18    cwd: PathBuf,
19    spec: AgentSpec,
20    mcp_config_sources: Vec<McpConfigSource>,
21    extra_mcp_servers: Vec<McpServer>,
22    oauth_applicator: Option<Box<dyn FnOnce(McpBuilder) -> McpBuilder + Send>>,
23    agent_deps: AgentDeps,
24    prompt_cache_key: Option<String>,
25}
26
27pub struct Runtime {
28    pub agent_tx: Sender<Command>,
29    pub agent_rx: Receiver<AgentEvent>,
30    pub agent_handle: AgentHandle,
31    pub mcp_tx: Sender<McpCommand>,
32    pub event_rx: Receiver<McpClientEvent>,
33    pub mcp_handle: JoinHandle<()>,
34}
35
36pub struct PromptInfo {
37    pub spec: AgentSpec,
38    pub tool_definitions: Vec<ToolDefinition>,
39}
40
41impl RuntimeBuilder {
42    pub fn new(cwd: &Path, model: &str) -> Result<Self, CliError> {
43        let cwd = cwd.canonicalize().map_err(CliError::IoError)?;
44        let parsed_model: LlmModel = model.parse().map_err(CliError::ModelError)?;
45        let spec = AgentSpec::default_spec(&parsed_model, None, Vec::new());
46
47        Ok(Self {
48            cwd,
49            spec,
50            mcp_config_sources: Vec::new(),
51            extra_mcp_servers: Vec::new(),
52            oauth_applicator: None,
53            agent_deps: AgentDeps::default(),
54            prompt_cache_key: None,
55        })
56    }
57
58    pub fn from_spec(cwd: PathBuf, spec: AgentSpec) -> Self {
59        Self {
60            cwd,
61            spec,
62            mcp_config_sources: Vec::new(),
63            extra_mcp_servers: Vec::new(),
64            oauth_applicator: None,
65            agent_deps: AgentDeps::default(),
66            prompt_cache_key: None,
67        }
68    }
69
70    pub fn prompt_cache_key(mut self, key: String) -> Self {
71        self.prompt_cache_key = Some(key);
72        self
73    }
74
75    pub fn agent_deps(mut self, deps: AgentDeps) -> Self {
76        self.agent_deps = deps;
77        self
78    }
79
80    /// Set MCP config source overrides. When non-empty, these completely
81    /// replace any sources resolved from the agent's `AgentSpec`.
82    pub fn mcp_sources(mut self, sources: Vec<McpConfigSource>) -> Self {
83        self.mcp_config_sources = sources;
84        self
85    }
86
87    pub fn extra_servers(mut self, servers: Vec<McpServer>) -> Self {
88        self.extra_mcp_servers = servers;
89        self
90    }
91
92    pub fn oauth_handler_factory(mut self, factory: OAuthHandlerFactory) -> Self {
93        self.oauth_applicator = Some(Box::new(|builder| builder.with_oauth_handler_factory(factory)));
94        self
95    }
96
97    pub async fn build(
98        self,
99        custom_prompt: Option<Prompt>,
100        messages: Option<Vec<ChatMessage>>,
101    ) -> Result<Runtime, CliError> {
102        let deps = self.agent_deps.clone();
103        let prompt_cache_key = self.prompt_cache_key.clone();
104        let (spec, spawn) = self.spawn_mcp().await?;
105        let McpSpawnResult { command_tx: mcp_tx, event_rx, handle: mcp_handle } = spawn;
106
107        let (agent_tx, agent_rx, agent_handle) =
108            spawn_agent(&spec, &deps, mcp_tx.clone(), Vec::new(), prompt_cache_key, |mut agent_builder| {
109                if let Some(prompt) = custom_prompt {
110                    agent_builder = agent_builder.system_prompt(prompt);
111                }
112                if let Some(msgs) = messages {
113                    agent_builder = agent_builder.messages(msgs);
114                }
115                agent_builder
116            })
117            .await?;
118
119        Ok(Runtime { agent_tx, agent_rx, agent_handle, mcp_tx, event_rx, mcp_handle })
120    }
121
122    /// Spawn MCP, block until every server finishes its initial connection,
123    /// then build an agent pre-seeded with the connection's filtered tools and
124    /// MCP instructions. Returns the live [`Runtime`] plus the bootstrap
125    /// snapshot. Unlike [`build`](Self::build) (which starts with no tools and
126    /// relies on the MCP event stream to populate them later), this is for
127    /// callers that need the agent ready to use tools on its first turn.
128    pub async fn build_ready(self, messages: Vec<ChatMessage>) -> Result<(Runtime, McpConnectionDetails), CliError> {
129        let deps = self.agent_deps.clone();
130        let prompt_cache_key = self.prompt_cache_key.clone();
131        let (spec, mut spawn) = self.spawn_mcp().await?;
132        let snapshot = spawn
133            .block_until_ready()
134            .await
135            .ok_or_else(|| CliError::McpError("MCP bootstrap aborted before completion".to_string()))?;
136        let McpSpawnResult { command_tx: mcp_tx, event_rx, handle: mcp_handle } = spawn;
137
138        let filtered_tools = spec.tools.apply(snapshot.tool_definitions.clone());
139        let mut runtime_spec = spec;
140        runtime_spec.prompts.push(Prompt::McpInstructions(snapshot.instructions.clone()));
141
142        let (agent_tx, agent_rx, agent_handle) =
143            spawn_agent(&runtime_spec, &deps, mcp_tx.clone(), filtered_tools, prompt_cache_key, |agent_builder| {
144                agent_builder.messages(messages)
145            })
146            .await?;
147
148        Ok((Runtime { agent_tx, agent_rx, agent_handle, mcp_tx, event_rx, mcp_handle }, snapshot))
149    }
150
151    pub async fn build_prompt_info(self) -> Result<PromptInfo, CliError> {
152        let (spec, mut spawn) = self.spawn_mcp().await?;
153        let details = spawn
154            .block_until_ready()
155            .await
156            .ok_or_else(|| CliError::McpError("MCP bootstrap aborted before completion".to_string()))?;
157        let filtered_tools = spec.tools.apply(details.tool_definitions);
158        Ok(PromptInfo { spec, tool_definitions: filtered_tools })
159    }
160
161    async fn spawn_mcp(self) -> Result<(AgentSpec, McpSpawnResult), CliError> {
162        let mut builder = mcp(&self.cwd).with_agent_deps(self.agent_deps.clone());
163
164        if let Some(apply_oauth) = self.oauth_applicator {
165            builder = apply_oauth(builder);
166        }
167
168        builder = builder.with_builtin_servers();
169
170        if !self.extra_mcp_servers.is_empty() {
171            builder = builder.with_servers(self.extra_mcp_servers);
172        }
173
174        let mcp_config_sources: Vec<McpConfigSource> = if self.mcp_config_sources.is_empty() {
175            self.spec.mcp_config_sources.clone()
176        } else {
177            self.mcp_config_sources
178        };
179
180        if !mcp_config_sources.is_empty() {
181            debug!("Loading MCP configs from: {:?}", mcp_config_sources);
182            builder = builder
183                .from_mcp_config_sources(&mcp_config_sources)
184                .await
185                .map_err(|e| CliError::McpError(e.to_string()))?;
186        }
187
188        let spawn = builder.spawn().await.map_err(|e| CliError::McpError(e.to_string()))?;
189        Ok((self.spec, spawn))
190    }
191}
192
193async fn spawn_agent(
194    spec: &AgentSpec,
195    deps: &AgentDeps,
196    mcp_tx: Sender<McpCommand>,
197    tool_definitions: Vec<ToolDefinition>,
198    prompt_cache_key: Option<String>,
199    configure: impl FnOnce(AgentBuilder) -> AgentBuilder,
200) -> Result<(Sender<Command>, Receiver<AgentEvent>, AgentHandle), CliError> {
201    let mut builder = AgentBuilder::from_spec(spec, vec![], deps)
202        .await
203        .map_err(|error| CliError::AgentError(error.to_string()))?
204        .tools(mcp_tx, tool_definitions);
205
206    if let Some(key) = prompt_cache_key {
207        builder = builder.prompt_cache_key(key);
208    }
209
210    configure(builder).spawn().await.map_err(|error| CliError::AgentError(error.to_string()))
211}
aether_cli/runtime.rs

aether_cli/
runtime.rs
