Dependencies API

The Dependencies API allows you to create, retrieve, update, and delete dependencies between items and external systems. Dependencies help track blocking relationships and manage project risks.

The Dependency Object

Name
id
Type
string
Description
Unique identifier for the dependency.
Name
sourceItemId
Type
string
Description
ID of the item that has the dependency.
Name
targetItemId
Type
string
Description
ID of the target item (null for external dependencies).
Name
dependencyType
Type
string
Description
Type: depends_on, blocks, related_to, prerequisite, successor.
Name
riskLevel
Type
string
Description
Risk level: low, medium, high, critical.
Name
status
Type
string
Description
Status: active, resolved, cancelled, blocked.
Name
isExternal
Type
boolean
Description
Whether this is an external dependency.
Name
externalTarget
Type
string
Description
Name of external system/vendor (for external dependencies).
Name
externalOwner
Type
string
Description
Contact person for external dependency.
Name
contactEmail
Type
string
Description
Email for external contact.
Name
vendor
Type
string
Description
Vendor or organization name.
Name
slaDate
Type
date
Description
Service level agreement date.
Name
escalationDate
Type
date
Description
Date to escalate if not resolved.
Name
notes
Type
string
Description
Additional notes about the dependency.
Name
createdAt
Type
timestamp
Description
When the dependency was created.
Name
createdByUserId
Type
string
Description
User who created the dependency.

GET/api/dependencies

List dependencies

This endpoint allows you to retrieve dependencies with various filtering options.

Query Parameters

Name
itemId
Type
string
Description
Filter by source item ID.
Name
sowId
Type
string
Description
Filter by SOW ID (all dependencies in a SOW).
Name
type
Type
string
Description
Filter by type: critical, overdue, external.
Name
status
Type
string
Description
Filter by status: active, resolved, cancelled, blocked.

Response

Returns an array of dependency objects.

cURL

curl https://api.tanda.app/api/dependencies?itemId=item_123 \
  -H "Authorization: Bearer {token}"

Response

[
  {
    "id": "dep_123",
    "sourceItemId": "item_123",
    "targetItemId": "item_456",
    "dependencyType": "depends_on",
    "riskLevel": "medium",
    "status": "active",
    "isExternal": false,
    "notes": "User auth must be complete before profile features",
    "createdAt": "2025-05-25T12:00:00Z"
  }
]

GET/api/dependencies/{dependencyId}

Retrieve a dependency

This endpoint allows you to retrieve a single dependency by its ID.

Path Parameters

Name
dependencyId
Type
string
Required
Description
The ID of the dependency to retrieve.

Response

Returns the dependency object if found.

cURL

curl https://api.tanda.app/api/dependencies/dep_123 \
  -H "Authorization: Bearer {token}"

Response

{
  "id": "dep_123",
  "sourceItemId": "item_123",
  "targetItemId": "item_456",
  "dependencyType": "depends_on",
  "riskLevel": "medium",
  "status": "active",
  "isExternal": false,
  "notes": "User auth must be complete before profile features",
  "createdAt": "2025-05-25T12:00:00Z",
  "createdByUserId": "user_789"
}

POST/api/dependencies

Create a dependency

This endpoint allows you to create a new dependency between items or with external systems.

Request Body

Name
sourceItemId
Type
string
Required
Description
ID of the item that has the dependency.
Name
targetItemId
Type
string
Description
ID of the target item (required for internal dependencies).
Name
dependencyType
Type
string
Required
Description
Type: depends_on, blocks, related_to, prerequisite, successor.
Name
riskLevel
Type
string
Required
Description
Risk level: low, medium, high, critical.
Name
isExternal
Type
boolean
Description
Set to true for external dependencies.
Name
externalTarget
Type
string
Description
Name of external system (required for external dependencies).
Name
externalOwner
Type
string
Description
Contact person for external dependency.
Name
contactEmail
Type
string
Description
Email for external contact.
Name
vendor
Type
string
Description
Vendor or organization name.
Name
slaDate
Type
date
Description
Service level agreement date.
Name
escalationDate
Type
date
Description
Date to escalate if not resolved.
Name
notes
Type
string
Description
Additional notes about the dependency.

Response

Returns the created dependency object.

cURL - Internal Dependency

curl -X POST https://api.tanda.app/api/dependencies \
  -H "Authorization: Bearer {token}" \
  -H "Content-Type: application/json" \
  -d '{
    "sourceItemId": "item_123",
    "targetItemId": "item_456",
    "dependencyType": "depends_on",
    "riskLevel": "medium",
    "notes": "Payment system needs user auth first"
  }'

cURL - External Dependency

curl -X POST https://api.tanda.app/api/dependencies \
  -H "Authorization: Bearer {token}" \
  -H "Content-Type: application/json" \
  -d '{
    "sourceItemId": "item_123",
    "isExternal": true,
    "externalTarget": "Stripe Payment Gateway",
    "externalOwner": "John Smith",
    "contactEmail": "john@stripe.com",
    "dependencyType": "depends_on",
    "riskLevel": "high",
    "vendor": "Stripe Inc",
    "slaDate": "2024-11-15",
    "escalationDate": "2024-11-10",
    "notes": "Need API access and webhooks configured"
  }'

Response

{
  "id": "dep_789",
  "sourceItemId": "item_123",
  "targetItemId": "item_456",
  "dependencyType": "depends_on",
  "riskLevel": "medium",
  "status": "active",
  "isExternal": false,
  "notes": "Payment system needs user auth first",
  "createdAt": "2025-05-25T13:00:00Z",
  "createdByUserId": "user_789"
}

PUT/api/dependencies/{dependencyId}

Update a dependency

This endpoint allows you to update an existing dependency.

Path Parameters

Name
dependencyId
Type
string
Required
Description
The ID of the dependency to update.

Request Body

Name
status
Type
string
Description
Updated status: active, resolved, cancelled, blocked.
Name
riskLevel
Type
string
Description
Updated risk level: low, medium, high, critical.
Name
slaDate
Type
date
Description
Updated SLA date.
Name
escalationDate
Type
date
Description
Updated escalation date.
Name
notes
Type
string
Description
Updated notes.

Response

Returns the updated dependency object.

cURL

curl -X PUT https://api.tanda.app/api/dependencies/dep_123 \
  -H "Authorization: Bearer {token}" \
  -H "Content-Type: application/json" \
  -d '{
    "status": "resolved",
    "notes": "Vendor completed API integration successfully"
  }'

Response

{
  "id": "dep_123",
  "sourceItemId": "item_123",
  "targetItemId": null,
  "dependencyType": "depends_on",
  "riskLevel": "high",
  "status": "resolved",
  "isExternal": true,
  "externalTarget": "Stripe Payment Gateway",
  "externalOwner": "John Smith",
  "notes": "Vendor completed API integration successfully",
  "createdAt": "2025-05-25T12:00:00Z",
  "updatedAt": "2025-05-25T14:00:00Z"
}

DELETE/api/dependencies/{dependencyId}

Delete a dependency

This endpoint allows you to delete a dependency.

Path Parameters

Name
dependencyId
Type
string
Required
Description
The ID of the dependency to delete.

Response

Returns a success message if the dependency was deleted.

cURL

curl -X DELETE https://api.tanda.app/api/dependencies/dep_123 \
  -H "Authorization: Bearer {token}"

Response

{
  "message": "Dependency deleted successfully"
}

GET/api/dependencies/chain

Get dependency chain

This endpoint returns the complete dependency chain for analysis and visualization.

Query Parameters

Name
sowId
Type
string
Required
Description
The ID of the SOW to analyze.
Name
format
Type
string
Description
Response format: tree, flat (default: flat).

Response

Returns the dependency chain showing relationships and potential issues.

cURL

curl https://api.tanda.app/api/dependencies/chain?sowId=sow_123 \
  -H "Authorization: Bearer {token}"

Response

{
  "sowId": "sow_123",
  "dependencies": [
    {
      "id": "dep_123",
      "sourceItem": {
        "id": "item_123",
        "title": "Payment System"
      },
      "targetItem": {
        "id": "item_456", 
        "title": "User Authentication"
      },
      "dependencyType": "depends_on",
      "riskLevel": "medium",
      "status": "active"
    }
  ],
  "issues": {
    "circular": [],
    "overdue": [],
    "critical": []
  }
}

Dependency Types

The API supports several dependency relationship types:

Internal Dependencies

depends_on: Source item needs target item to be completed
blocks: Source item prevents target item from starting
related_to: Items are related but not strictly blocking
prerequisite: Target item must be done before source item
successor: Source item comes after target item

External Dependencies

All relationship types apply, but the target is an external system rather than an internal item.

Risk Levels

low: Minor impact if delayed, easy workarounds available
medium: Moderate impact, some workarounds possible
high: Significant impact on timeline or deliverables
critical: Project-blocking, no viable workarounds

Status Values

active: Dependency is current and blocking
resolved: Dependency has been satisfied
cancelled: Dependency is no longer relevant
blocked: Dependency cannot be resolved due to external factors

Filtering Options

Get critical dependencies

GET /api/dependencies?sowId=sow_123&type=critical

Get overdue dependencies

GET /api/dependencies?sowId=sow_123&type=overdue

Get external dependencies

GET /api/dependencies?sowId=sow_123&type=external

Get dependencies for specific item

GET /api/dependencies?itemId=item_123

Circular Dependency Prevention

The API automatically prevents circular dependencies. If you attempt to create a dependency that would result in a circular relationship, the request will be rejected with a 400 Bad Request error.

Example circular dependency that would be rejected:

Item A depends on Item B
Item B depends on Item C  
Item C depends on Item A ← This would be rejected

Error Responses

The API uses standard HTTP status codes:

200 OK - Request succeeded
201 Created - Dependency created successfully
400 Bad Request - Invalid request or circular dependency detected
401 Unauthorized - Missing or invalid authentication
403 Forbidden - Insufficient permissions
404 Not Found - Dependency or item not found
500 Internal Server Error - Server error

Error responses include descriptive messages:

{
  "error": "Circular dependency detected: item_123 → item_456 → item_123"
}