Struct Event 

pub struct Event {

    pub id: Option<i64>,
    pub machine_id: String,
    pub timestamp: DateTime<Utc>,
    pub event_type: EventType,
    pub session_id: String,
    pub framework: Option<String>,
    pub tool_use_id: Option<String>,
    pub spawned_agent_id: Option<String>,
    pub tool_name: Option<String>,
    pub subagent_type: Option<String>,
    pub permission_mode: Option<String>,
    pub transcript_path: Option<String>,
    pub pid: Option<i32>,
    pub process_start_time: Option<i64>,
    pub cwd: Option<String>,
    pub git_branch: Option<String>,
    pub model: Option<String>,
    pub tokens_input: Option<i64>,
    pub tokens_output: Option<i64>,
    pub tokens_cache_read: Option<i64>,
    pub tokens_cache_write: Option<i64>,
    pub cost_usd: Option<f64>,
    pub duration_ms: Option<i64>,
    pub payload: Option<String>,
    pub metadata: Option<String>,
    pub source: Option<String>,
    pub is_sidechain: Option<bool>,
    pub context_size: Option<i64>,
}

A hook event captured from Claude Code

Fields

id: Option<i64>

Database ID (None for new events)

machine_id: String

Machine identifier for multi-machine sync

timestamp: DateTime<Utc>

Event timestamp

event_type: EventType

Event type (SessionStart, PreToolUse, etc.)

session_id: String

Session ID from Claude Code

framework: Option<String>

Source framework (claude, cursor, gemini, etc.)

tool_use_id: Option<String>

Tool use ID for correlating PreToolUse/PostToolUse

spawned_agent_id: Option<String>

Child agent ID from PostToolUse for Task tool (links parent → child sessions)

tool_name: Option<String>

Tool name (Bash, Read, Write, Edit, Task, etc.)

subagent_type: Option<String>

Subagent type for Task tool (Explore, Plan, claude-code-guide, etc.)

permission_mode: Option<String>

Permission mode (default, plan, acceptEdits, bypassPermissions)

transcript_path: Option<String>

Path to the session transcript JSONL file

pid: Option<i32>

Parent process ID

process_start_time: Option<i64>

Process start time in seconds (Unix timestamp). Captured at event ingestion time for session identity validation.

Note: This field is a transport mechanism - it’s captured during event ingestion but only persisted to the sessions table, not the events table. Used to populate Session::process_start_time for PID identity validation.

cwd: Option<String>

Working directory

git_branch: Option<String>

Git branch name

model: Option<String>

Model used for API request (e.g., “claude-3-opus”)

tokens_input: Option<i64>

Input tokens used

tokens_output: Option<i64>

Output tokens generated

tokens_cache_read: Option<i64>

Tokens read from cache

tokens_cache_write: Option<i64>

Tokens written to cache

cost_usd: Option<f64>

Cost in USD

duration_ms: Option<i64>

API call duration in milliseconds

payload: Option<String>

JSON payload with all hook data

metadata: Option<String>

Extensible JSON metadata for future fields

source: Option<String>

Data source: ‘hook’, ‘otel’, or ‘transcript’

is_sidechain: Option<bool>

Whether this is a sidechain request (subagent/auxiliary) Only available from transcript parsing - critical for context size tracking

context_size: Option<i64>

Context window size (total tokens in conversation). Used by Amp thread reader where context is pre-calculated from thread data.

Implementations

impl Event

pub fn new( machine_id: String, event_type: EventType, session_id: String, ) -> Self

Create a new event with current timestamp

pub fn is_api_request(&self) -> bool

Check if this event is an API request (has token data)

pub fn total_tokens(&self) -> i64

Total tokens (input + output) for API requests

pub fn is_main_chain(&self) -> bool

Returns true if this is a transcript event from the main conversation chain.

Main chain events are the primary conversation between user and agent. Sidechain events are subagent/auxiliary requests that run in parallel.

This is used for filtering when updating session context - we only want to update context (issue/PR numbers, branch info) from main chain events.

Returns true if:

• The event source is “transcript” AND
• The event is NOT marked as sidechain (is_sidechain != Some(true))

Note: Only transcript events have reliable sidechain info. Hook and OTEL events don’t have this field, so this method returns false for them.

pub fn is_sidechain_event(&self) -> bool

Returns true if this is a transcript event from a sidechain (subagent).

Sidechain events are subagent requests that run in parallel to the main conversation. They should not update session context.

Note: Only transcript events have reliable sidechain info.

Trait Implementations

impl Clone for Event

fn clone(&self) -> Event

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Event

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Event

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for Event

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.