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aether_core/events/
agent_event.rs

1use schemars::JsonSchema;
2use serde::{Deserialize, Serialize};
3
4use super::{ContextEvent, MessageEvent, ModelEvent, StreamState, ToolEvent, TurnEvent, TurnOutcome};
5
6/// A canonical event on the agent's output stream.
7#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
8#[serde(tag = "category", content = "event", rename_all = "snake_case")]
9#[allow(clippy::large_enum_variant)]
10pub enum AgentEvent {
11    Message(MessageEvent),
12    Tool(ToolEvent),
13    Turn(TurnEvent),
14    Context(ContextEvent),
15    Model(ModelEvent),
16    SessionUsage(llm::SessionUsageEvent),
17}
18
19impl AgentEvent {
20    pub fn text(message_id: &str, chunk: &str, state: StreamState) -> Self {
21        Self::Message(MessageEvent::Text {
22            message_id: message_id.into(),
23            chunk: chunk.into(),
24            is_complete: state.is_complete(),
25        })
26    }
27
28    pub fn thought(message_id: &str, chunk: &str, state: StreamState) -> Self {
29        Self::Message(MessageEvent::Thought {
30            message_id: message_id.into(),
31            chunk: chunk.into(),
32            is_complete: state.is_complete(),
33        })
34    }
35
36    pub fn turn_ended(outcome: TurnOutcome) -> Self {
37        Self::Turn(TurnEvent::Ended { outcome })
38    }
39
40    /// Human-readable text content of this event, if any.
41    pub fn content(&self) -> Option<String> {
42        match self {
43            Self::Message(MessageEvent::Text { chunk, .. } | MessageEvent::Thought { chunk, .. }) => {
44                Some(chunk.clone())
45            }
46            Self::Tool(ToolEvent::Result { result, .. } | ToolEvent::TaskCompleted { result, .. }) => {
47                Some(result.result.clone())
48            }
49            Self::Tool(ToolEvent::Error { error } | ToolEvent::TaskFailed { error, .. }) => Some(error.error.clone()),
50            Self::Tool(ToolEvent::TaskCreated { task_id, .. }) => Some(task_id.clone()),
51            Self::Tool(ToolEvent::TaskStatus { task_id, status, status_message, .. }) => {
52                Some(status_message.as_ref().map_or_else(
53                    || format!("{task_id}: {status}"),
54                    |message| format!("{task_id}: {status} - {message}"),
55                ))
56            }
57            Self::Tool(ToolEvent::TaskCancelled { task_id, .. }) => Some(format!("{task_id}: cancelled")),
58            Self::Context(ContextEvent::CompactionResult { summary, .. }) => Some(summary.clone()),
59            _ => None,
60        }
61    }
62
63    /// The turn's terminal outcome, if this event ends a turn.
64    pub fn turn_outcome(&self) -> Option<&TurnOutcome> {
65        match self {
66            Self::Turn(TurnEvent::Ended { outcome }) => Some(outcome),
67            _ => None,
68        }
69    }
70
71    pub fn is_stream_delta(&self) -> bool {
72        matches!(
73            self,
74            Self::Message(
75                MessageEvent::Text { is_complete: false, .. } | MessageEvent::Thought { is_complete: false, .. }
76            ) | Self::Tool(ToolEvent::InputDelta { .. })
77        )
78    }
79}
80
81#[cfg(test)]
82mod tests {
83    use super::*;
84    use crate::events::{CompactionOutcome, LlmCallOutcome};
85    use llm::{ContextUsage, LlmCallPurpose};
86    use utils::display_meta::ToolDisplayMeta;
87
88    #[test]
89    fn serializes_nested_event_contract() {
90        let event = AgentEvent::text("m1", "hello", StreamState::Complete);
91        assert_eq!(
92            serde_json::to_value(event).unwrap(),
93            serde_json::json!({"category":"message","event":{"type":"text","message_id":"m1","chunk":"hello","is_complete":true}})
94        );
95    }
96
97    #[test]
98    fn nested_events_roundtrip() {
99        let events = [
100            AgentEvent::text("m", "text", StreamState::Complete),
101            AgentEvent::Tool(ToolEvent::DefinitionsUpdated { tools: vec![] }),
102            AgentEvent::Turn(TurnEvent::LlmCallEnded {
103                purpose: LlmCallPurpose::Chat,
104                outcome: LlmCallOutcome::Cancelled,
105            }),
106            AgentEvent::Context(ContextEvent::UsageUpdated { usage: ContextUsage::default() }),
107            AgentEvent::Context(ContextEvent::CompactionEnded {
108                compaction_id: "compaction".into(),
109                outcome: CompactionOutcome::Completed,
110            }),
111            AgentEvent::Model(ModelEvent::Switched { previous: "a".into(), new: "b".into() }),
112            AgentEvent::SessionUsage(llm::testing::session_usage_event(1, llm::TokenUsage::new(1, 2))),
113            AgentEvent::Tool(ToolEvent::DisplayUpdate {
114                request: llm::ToolCallRequest { id: "call".into(), name: "read".into(), arguments: "{}".into() },
115                meta: ToolDisplayMeta::new("Read file", "main.rs").into(),
116            }),
117            AgentEvent::Tool(ToolEvent::SubAgentProgress {
118                request: llm::ToolCallRequest { id: "call".into(), name: "spawn".into(), arguments: "{}".into() },
119                payload: Box::new(crate::events::SubAgentProgressPayload {
120                    task_id: "task_0".into(),
121                    agent_name: "explorer".into(),
122                    event: AgentEvent::turn_ended(TurnOutcome::Completed),
123                }),
124            }),
125        ];
126        for event in events {
127            let json = serde_json::to_string(&event).unwrap();
128            assert_eq!(serde_json::from_str::<AgentEvent>(&json).unwrap(), event);
129        }
130    }
131
132    #[test]
133    fn failed_call_ended_serializes_diagnostics_and_omits_absent_fields() {
134        let event = AgentEvent::Turn(TurnEvent::LlmCallEnded {
135            purpose: LlmCallPurpose::Chat,
136            outcome: LlmCallOutcome::Failed {
137                error: "Server error: boom (status 200, code server_error, request_id req-1)".into(),
138                will_retry: true,
139                http_status: Some(200),
140                provider_request_id: Some("req-1".into()),
141                provider_error_code: Some("server_error".into()),
142            },
143        });
144        assert_eq!(
145            serde_json::to_value(&event).unwrap(),
146            serde_json::json!({
147                "category": "turn",
148                "event": {
149                    "type": "llm_call_ended",
150                    "purpose": "chat",
151                    "outcome": {
152                        "status": "failed",
153                        "error": "Server error: boom (status 200, code server_error, request_id req-1)",
154                        "will_retry": true,
155                        "http_status": 200,
156                        "provider_request_id": "req-1",
157                        "provider_error_code": "server_error"
158                    }
159                }
160            })
161        );
162
163        let minimal = AgentEvent::Turn(TurnEvent::LlmCallEnded {
164            purpose: LlmCallPurpose::Chat,
165            outcome: LlmCallOutcome::failed("boom", false),
166        });
167        let value = serde_json::to_value(&minimal).unwrap();
168        let outcome = &value["event"]["outcome"];
169        assert_eq!(outcome["status"], "failed");
170        assert!(outcome.get("http_status").is_none());
171        assert!(outcome.get("provider_request_id").is_none());
172        assert!(outcome.get("provider_error_code").is_none());
173        assert_eq!(serde_json::from_value::<AgentEvent>(value).unwrap(), minimal);
174    }
175
176    #[test]
177    fn from_llm_error_copies_provider_diagnostics() {
178        let provider = llm::ProviderError::server("boom")
179            .with_http_status(503)
180            .with_request_id(Some("req-9".into()))
181            .with_code(Some("server_error".into()));
182        let outcome = LlmCallOutcome::from_llm_error(&llm::LlmError::from(provider), true);
183        match outcome {
184            LlmCallOutcome::Failed { http_status, provider_request_id, provider_error_code, will_retry, .. } => {
185                assert!(will_retry);
186                assert_eq!(http_status, Some(503));
187                assert_eq!(provider_request_id.as_deref(), Some("req-9"));
188                assert_eq!(provider_error_code.as_deref(), Some("server_error"));
189            }
190            _ => panic!("expected failed outcome"),
191        }
192        let terminal = LlmCallOutcome::from_llm_error(&llm::LlmError::InvalidArgument("bad".into()), false);
193        match terminal {
194            LlmCallOutcome::Failed { http_status, provider_request_id, provider_error_code, .. } => {
195                assert_eq!(http_status, None);
196                assert_eq!(provider_request_id, None);
197                assert_eq!(provider_error_code, None);
198            }
199            _ => panic!("expected failed outcome"),
200        }
201    }
202
203    #[test]
204    fn turn_outcome_returns_outcome_only_for_turn_end() {
205        assert_eq!(AgentEvent::turn_ended(TurnOutcome::Completed).turn_outcome(), Some(&TurnOutcome::Completed));
206        assert_eq!(AgentEvent::text("m", "text", StreamState::Complete).turn_outcome(), None);
207        assert_eq!(AgentEvent::Turn(TurnEvent::Started { content: vec![] }).turn_outcome(), None);
208    }
209
210    #[test]
211    fn only_partial_chunks_and_tool_input_deltas_are_stream_deltas() {
212        let deltas = [
213            AgentEvent::text("m", "par", StreamState::Partial),
214            AgentEvent::thought("m", "par", StreamState::Partial),
215            AgentEvent::Tool(ToolEvent::InputDelta { id: "call".into(), chunk: "{".into() }),
216        ];
217        let complete = [
218            AgentEvent::text("m", "partial", StreamState::Complete),
219            AgentEvent::thought("m", "partial", StreamState::Complete),
220            AgentEvent::Tool(ToolEvent::InputStarted { id: "call".into(), name: "read".into() }),
221            AgentEvent::Tool(ToolEvent::Call {
222                request: llm::ToolCallRequest { id: "call".into(), name: "read".into(), arguments: "{}".into() },
223            }),
224            AgentEvent::turn_ended(TurnOutcome::Completed),
225        ];
226        assert!(deltas.iter().all(AgentEvent::is_stream_delta));
227        assert!(!complete.iter().any(AgentEvent::is_stream_delta));
228    }
229}