Version: 1.1.5

Activity Log API

The Activity Log API provides an append-only audit trail of all actions across the Symphony system. It records events like task creation, milestone completion, project updates, and webhook registration, enabling compliance, debugging, and analytics use cases.

Design principles

Append-only: No update (PATCH/PUT) or delete operations — audit logs are immutable once created.
Newest first: All list responses are sorted by timestamp in descending order.
Rich filtering: Query by action type, actor, resource type, resource ID, and time ranges.
Pagination support: Use ?limit= to control result size while maintaining access to the full count via the total field.

Data model

Field	Type	Description
`id`	`string`	Unique identifier (e.g. `act_a1b2c3d4`)
`action`	`string`	Structured action type (e.g. `task.status_changed`, `milestone.reached`)
`actor`	`string`	Username or system identifier that performed the action
`resourceType`	`string`	Type of resource affected (e.g. `task`, `project`, `milestone`)
`resourceId`	`string`	ID of the affected resource (e.g. `task_01`)
`summary`	`string`	Human-readable description of the action
`metadata`	`object`	Additional context (e.g. `{"from": "todo", "to": "done"}`)
`timestamp`	`string`	ISO 8601 timestamp when the action occurred

Common action types

Action	Example resource types	Description
`*.created`	`task`, `project`, `comment`, `webhook`	Resource created
`*.updated`	`project`, `task`	Resource modified
`*.deleted`	`task`, `comment`	Resource removed
`*.status_changed`	`task`	Status transition
`*.assigned`	`task`	Assignment changed
`milestone.reached`	`milestone`	Milestone marked as complete
`sprint.started`	`sprint`	Sprint initiated
`sprint.completed`	`sprint`	Sprint finished

The metadata field captures action-specific details. For example:

task.status_changed includes {"from": "todo", "to": "done"}
webhook.created includes {"events": ["task.created", "task.updated"]}
milestone.reached includes {"projectId": "proj_01"}

Endpoints

List activity log entries

GET /api/activity-log

Returns activities sorted newest-first.

Query parameters:

Parameter	Type	Description
`action`	`string`	Filter to specific action type (e.g. `milestone.reached`)
`actor`	`string`	Filter by username/actor (e.g. `alice`)
`resourceType`	`string`	Filter by resource type (e.g. `task`, `project`)
`resourceId`	`string`	Filter by specific resource ID (e.g. `task_01`)
`since`	`string`	ISO 8601 timestamp — only include activities at or after this time
`until`	`string`	ISO 8601 timestamp — only include activities at or before this time
`limit`	`number`	Maximum number of results to return

Response: 200 OK

{
  "data": [
    {
      "id": "act_09",
      "action": "task.deleted",
      "actor": "charlie",
      "resourceType": "task",
      "resourceId": "task_99",
      "summary": "charlie deleted a deprecated task",
      "metadata": {},
      "timestamp": "2026-02-15T11:00:00Z"
    },
    {
      "id": "act_05",
      "action": "project.updated",
      "actor": "bob",
      "resourceType": "project",
      "resourceId": "proj_04",
      "summary": "bob updated project \"Data Pipeline Overhaul\"",
      "metadata": { "fields": ["description"] },
      "timestamp": "2026-02-10T09:20:00Z"
    }
  ],
  "count": 2,
  "total": 10
}

count: Number of entries in this response (respects limit)
total: Total number of matching entries before limit applied

Get single activity entry

GET /api/activity-log/:id

Response: 200 OK with the activity object.

Error: 404 Not Found with error code NOT_FOUND if the entry does not exist.

Create activity entry

POST /api/activity-log

Records a new activity. The id is auto-generated and timestamp is set to the current server time.

Request body:

{
  "action": "task.status_changed",
  "actor": "alice",
  "resourceType": "task",
  "resourceId": "task_01",
  "summary": "alice changed task status from todo to done",
  "metadata": { "from": "todo", "to": "done" }
}

Field	Required	Default
`action`	yes	—
`actor`	yes	—
`resourceType`	yes	—
`resourceId`	yes	—
`summary`	no	`""`
`metadata`	no	`{}`

Response: 201 Created

{
  "data": {
    "id": "act_a1b2c3d4",
    "action": "task.status_changed",
    "actor": "alice",
    "resourceType": "task",
    "resourceId": "task_01",
    "summary": "alice changed task status from todo to done",
    "metadata": { "from": "todo", "to": "done" },
    "timestamp": "2026-02-19T10:15:32Z"
  }
}

Note: There is no update (PATCH/PUT) or delete operation for activity log entries. Once created, they are immutable.

Examples

List all activities (newest first)

curl http://localhost:3000/api/activity-log

Filter by actor

curl "http://localhost:3000/api/activity-log?actor=alice"

Returns all activities performed by user alice.

Filter by action type

curl "http://localhost:3000/api/activity-log?action=milestone.reached"

Returns only milestone completion events.

Filter by resource

curl "http://localhost:3000/api/activity-log?resourceType=task&resourceId=task_01"

Returns all activities related to task task_01.

Time range query

curl "http://localhost:3000/api/activity-log?since=2026-01-01T00:00:00Z&until=2026-01-31T23:59:59Z"

Returns activities that occurred in January 2026.

Limit results

curl "http://localhost:3000/api/activity-log?limit=5"

Returns the 5 most recent activities. The total field in the response shows how many activities exist in total.

Create an activity log entry

curl -X POST http://localhost:3000/api/activity-log \
  -H "Content-Type: application/json" \
  -d '{
    "action": "project.created",
    "actor": "alice",
    "resourceType": "project",
    "resourceId": "proj_10",
    "summary": "alice created project \"Mobile App Redesign\"",
    "metadata": { "template": "agile" }
  }'

Use cases

Compliance and audit trails

Query all actions within a specific time period for compliance reporting:

curl "http://localhost:3000/api/activity-log?since=2026-01-01T00:00:00Z&until=2026-03-31T23:59:59Z"

User activity tracking

Monitor all actions by a specific user:

curl "http://localhost:3000/api/activity-log?actor=alice"

Resource history

View the complete history of a specific resource:

curl "http://localhost:3000/api/activity-log?resourceType=task&resourceId=task_01"

Event-driven integrations

After performing an action through the API (e.g. creating a task), log it to the activity trail:

# 1. Create a task
curl -X POST http://localhost:3000/api/tasks \
  -H "Content-Type: application/json" \
  -d '{"title": "New feature", "status": "todo"}'

# 2. Log the activity
curl -X POST http://localhost:3000/api/activity-log \
  -H "Content-Type: application/json" \
  -d '{
    "action": "task.created",
    "actor": "alice",
    "resourceType": "task",
    "resourceId": "task_15",
    "summary": "alice created task \"New feature\""
  }'

Design principles​

Data model​

Common action types​

Endpoints​

List activity log entries​

Get single activity entry​

Create activity entry​

Examples​

List all activities (newest first)​

Filter by actor​

Filter by action type​

Filter by resource​

Time range query​

Limit results​

Create an activity log entry​

Use cases​

Compliance and audit trails​

User activity tracking​

Resource history​

Event-driven integrations​