gh-macroman5-automationhelper-plugins/.claude/skills/automation-debugger/ERROR-PATTERNS.md

Power Automate Error Patterns Reference

Quick reference guide for common Power Automate error patterns and their solutions.

Authentication Errors (401/403)

Pattern Recognition

• Status codes: 401, 403
• Error messages containing: "unauthorized", "forbidden", "access denied", "authentication failed"
• Common in: SharePoint, OneDrive, HTTP with authentication

Research Targets

PowerAutomateDocs/{Connector}/overview.md → Authentication section
PowerAutomateDocs/{Connector}/actions.md → Permission requirements

Common Root Causes

1. Expired or invalid credentials

   • Connection needs re-authentication
   • Credentials rotated but connection not updated

2. Insufficient permissions

   • Service account lacks required permissions
   • SharePoint: Need "Edit" or "Full Control" on list
   • OneDrive: Need appropriate file/folder permissions

3. Conditional access policies

   • Azure AD policies blocking service accounts
   • MFA requirements not met
   • Location-based restrictions

Fix Patterns

{
  "actions": {
    "Scope_Error_Handling": {
      "type": "Scope",
      "actions": {
        "Get_Items": {
          // Original action
        }
      },
      "runAfter": {}
    },
    "Catch_Auth_Error": {
      "type": "Compose",
      "inputs": "Authentication failed - verify connection permissions",
      "runAfter": {
        "Scope_Error_Handling": ["Failed", "TimedOut"]
      }
    }
  }
}

Throttling Errors (429)

Pattern Recognition

• Status code: 429
• Error messages: "TooManyRequests", "throttled", "rate limit exceeded"
• Common in: SharePoint (600/min), OneDrive (100/min), HTTP APIs

Research Targets

PowerAutomateDocs/{Connector}/overview.md → API Limits section
PowerAutomateDocs/BuiltIn/control.md → Delay actions

Connector-Specific Limits

Connector	Limit	Per
SharePoint	600 calls	60 seconds per connection
OneDrive	100 calls	60 seconds per connection
HTTP	600 calls	60 seconds (default)
Apply to each	50 iterations	Concurrent (default)

Fix Patterns

1. Add Delays Between Calls

{
  "actions": {
    "Delay": {
      "type": "Wait",
      "inputs": {
        "interval": {
          "count": 1,
          "unit": "Second"
        }
      },
      "runAfter": {
        "Previous_Action": ["Succeeded"]
      }
    }
  }
}

2. Implement Exponential Backoff

{
  "actions": {
    "Do_Until_Success": {
      "type": "Until",
      "expression": "@equals(variables('Success'), true)",
      "limit": {
        "count": 5,
        "timeout": "PT1H"
      },
      "actions": {
        "Try_Action": {
          "type": "ApiConnection",
          "inputs": { /* action config */ }
        },
        "Check_Status": {
          "type": "If",
          "expression": {
            "and": [
              {
                "equals": [
                  "@outputs('Try_Action')['statusCode']",
                  429
                ]
              }
            ]
          },
          "actions": {
            "Wait_Exponential": {
              "type": "Wait",
              "inputs": {
                "interval": {
                  "count": "@mul(2, variables('RetryCount'))",
                  "unit": "Second"
                }
              }
            }
          }
        }
      }
    }
  }
}

3. Reduce Concurrent Iterations

{
  "Apply_to_each": {
    "type": "Foreach",
    "foreach": "@body('Get_Items')",
    "runtimeConfiguration": {
      "concurrency": {
        "repetitions": 1
      }
    },
    "actions": { /* ... */ }
  }
}

Data Format Errors

Pattern Recognition

• Error messages: "InvalidTemplate", "Unable to process template", "cannot be evaluated", "property doesn't exist"
• Common in: Parse JSON, Compose, expressions with dynamic content

Research Targets

PowerAutomateDocs/BuiltIn/data-operation.md → Parse JSON section
PowerAutomateDocs/BuiltIn/data-operation.md → Compose section

Common Root Causes

1. Missing Parse JSON Schema

   • Dynamic content not available without schema
   • Schema doesn't match actual data structure

2. Incorrect Expression Syntax

   • Invalid Power Automate expression functions
   • Wrong property paths in JSON
   • Type mismatches (string vs number vs array)

3. Null/Undefined Values

   • Expressions trying to access null properties
   • Missing optional fields

Fix Patterns

1. Add Parse JSON with Proper Schema

{
  "Parse_JSON": {
    "type": "ParseJson",
    "inputs": {
      "content": "@body('HTTP')",
      "schema": {
        "type": "object",
        "properties": {
          "id": {
            "type": "string"
          },
          "name": {
            "type": "string"
          },
          "items": {
            "type": "array",
            "items": {
              "type": "object",
              "properties": {
                "value": {
                  "type": "string"
                }
              }
            }
          }
        }
      }
    }
  }
}

2. Add Null Checks in Expressions

{
  "Compose_Safe": {
    "type": "Compose",
    "inputs": "@if(not(empty(body('Parse_JSON')?['property'])), body('Parse_JSON')['property'], 'default_value')"
  }
}

3. Use Proper Type Conversions

{
  "Convert_To_String": {
    "type": "Compose",
    "inputs": "@string(variables('NumberValue'))"
  },
  "Convert_To_Int": {
    "type": "Compose",
    "inputs": "@int(variables('StringValue'))"
  }
}

Timeout Errors

Pattern Recognition

• Error messages: "timeout", "timed out", "operation took too long"
• Common in: Large file operations, long-running HTTP calls, Do until loops

Research Targets

PowerAutomateDocs/{Connector}/overview.md → Known Limitations
PowerAutomateDocs/BuiltIn/control.md → Do until limits

Connector-Specific Limits

Operation	Timeout
OneDrive file triggers	50MB max file size
SharePoint attachments	90MB max size
HTTP actions	2 minutes default
Do until loops	No default (must set)

Fix Patterns

1. Add Timeout Configuration

{
  "Do_Until": {
    "type": "Until",
    "expression": "@equals(variables('Complete'), true)",
    "limit": {
      "count": 60,
      "timeout": "PT1H"
    },
    "actions": { /* ... */ }
  }
}

2. Implement Chunking for Large Operations

{
  "Apply_to_each_Batch": {
    "type": "Foreach",
    "foreach": "@chunk(body('Get_Items'), 100)",
    "actions": {
      "Process_Batch": {
        "type": "Scope",
        "actions": { /* Process smaller batch */ }
      }
    }
  }
}

3. Add File Size Check

{
  "Check_File_Size": {
    "type": "If",
    "expression": {
      "and": [
        {
          "lessOrEquals": [
            "@triggerBody()?['Size']",
            52428800
          ]
        }
      ]
    },
    "actions": {
      "Process_File": { /* ... */ }
    },
    "else": {
      "actions": {
        "Handle_Large_File": { /* Alternative approach */ }
      }
    }
  }
}

Not Found Errors (404)

Pattern Recognition

• Status code: 404
• Error messages: "not found", "does not exist", "cannot find"
• Common in: SharePoint Get Item, OneDrive Get File Content, HTTP calls

Research Targets

PowerAutomateDocs/{Connector}/actions.md → Specific action requirements
PowerAutomateDocs/{Connector}/overview.md → Naming conventions

Common Root Causes

1. Incorrect Resource Paths/IDs

   • Hardcoded IDs that don't exist
   • Wrong site URLs
   • Invalid file paths

2. Permissions

   • User lacks read access to resource
   • Resource moved or deleted

3. SharePoint-Specific Issues

   • List names with periods (.) cause errors
   • Special characters in file names
   • Spaces in URLs not encoded

Fix Patterns

1. Add Existence Check

{
  "Try_Get_Item": {
    "type": "Scope",
    "actions": {
      "Get_Item": {
        "type": "ApiConnection",
        "inputs": { /* ... */ }
      }
    }
  },
  "Check_If_Failed": {
    "type": "If",
    "expression": {
      "and": [
        {
          "equals": [
            "@result('Try_Get_Item')[0]['status']",
            "Failed"
          ]
        }
      ]
    },
    "runAfter": {
      "Try_Get_Item": ["Failed", "Succeeded"]
    },
    "actions": {
      "Handle_Not_Found": {
        "type": "Compose",
        "inputs": "Item not found - creating new one"
      }
    }
  }
}

2. Use Dynamic IDs from Previous Actions

{
  "Get_Items": {
    "type": "ApiConnection",
    "inputs": { /* Get items first */ }
  },
  "Apply_to_each": {
    "type": "Foreach",
    "foreach": "@outputs('Get_Items')?['body/value']",
    "actions": {
      "Get_Item_Detail": {
        "type": "ApiConnection",
        "inputs": {
          "host": {
            "connectionName": "shared_sharepointonline"
          },
          "method": "get",
          "path": "/datasets/@{encodeURIComponent(variables('SiteURL'))}/tables/@{encodeURIComponent(variables('ListID'))}/items/@{items('Apply_to_each')?['ID']}"
        }
      }
    }
  }
}

Permission Errors (403)

Pattern Recognition

• Status code: 403
• Error messages: "forbidden", "access denied", "insufficient permissions"
• Different from 401 (authentication vs authorization)

Research Targets

PowerAutomateDocs/{Connector}/actions.md → Required permissions
PowerAutomateDocs/{Connector}/overview.md → Permission scopes

Common Root Causes

1. SharePoint Permissions

   • Need "Edit" for Create/Update/Delete
   • Need "Read" for Get operations
   • Site-level vs list-level permissions

2. OneDrive Permissions

   • Need write access for file operations
   • Shared folders require special handling

3. Delegated vs Application Permissions

   • Service accounts need proper permission grants
   • Azure AD application permissions

Fix Patterns

1. Verify and Document Required Permissions

{
  "actions": {
    "Comment_Permissions": {
      "type": "Compose",
      "inputs": "This flow requires: SharePoint site collection admin or list owner permissions"
    },
    "Try_Action_With_Permission": {
      "type": "Scope",
      "actions": { /* Action requiring permissions */ }
    },
    "Handle_Permission_Error": {
      "type": "If",
      "expression": {
        "and": [
          {
            "equals": [
              "@result('Try_Action_With_Permission')[0]['code']",
              "Forbidden"
            ]
          }
        ]
      },
      "runAfter": {
        "Try_Action_With_Permission": ["Failed", "Succeeded"]
      },
      "actions": {
        "Send_Permission_Request": {
          "type": "ApiConnection",
          "inputs": { /* Send email to admin */ }
        }
      }
    }
  }
}

Invalid JSON/Syntax Errors

Pattern Recognition

• Error messages: "Invalid JSON", "syntax error", "unexpected token"
• Common in: HTTP response parsing, JSON composition, dynamic expression building

Research Targets

PowerAutomateDocs/BuiltIn/data-operation.md → JSON handling
PowerAutomateDocs/power-automate-json-format.md → Valid structure

Fix Patterns

1. Escape Special Characters

{
  "Compose_JSON_String": {
    "type": "Compose",
    "inputs": "@{replace(variables('TextWithQuotes'), '\"', '\\\"')}"
  }
}

2. Validate JSON Before Parsing

{
  "Try_Parse": {
    "type": "Scope",
    "actions": {
      "Parse_JSON": {
        "type": "ParseJson",
        "inputs": {
          "content": "@body('HTTP')"
        }
      }
    }
  },
  "Handle_Invalid_JSON": {
    "type": "If",
    "expression": {
      "and": [
        {
          "equals": [
            "@result('Try_Parse')[0]['status']",
            "Failed"
          ]
        }
      ]
    },
    "runAfter": {
      "Try_Parse": ["Failed", "Succeeded"]
    },
    "actions": {
      "Log_Invalid_Response": {
        "type": "Compose",
        "inputs": "Invalid JSON received from API"
      }
    }
  }
}

Cross-Reference Matrix

Error Code	Error Type	Primary Research Location	Common Connectors
401	Authentication	{Connector}/overview.md	SharePoint, OneDrive, HTTP
403	Permission	{Connector}/actions.md	SharePoint, OneDrive
404	Not Found	{Connector}/actions.md	SharePoint, OneDrive, HTTP
429	Throttling	{Connector}/overview.md	SharePoint, OneDrive, HTTP
500	Server Error	{Connector}/overview.md	HTTP, SharePoint
N/A	Data Format	BuiltIn/data-operation.md	Parse JSON, Compose
N/A	Timeout	BuiltIn/control.md	Do Until, HTTP
N/A	Expression Error	BuiltIn/data-operation.md	All actions

Usage in Debugger Skill

This reference should be consulted during Phase 1 (Error Analysis) to:

1. Quickly classify the error type
2. Identify relevant research targets
3. Understand common root causes
4. Reference appropriate fix patterns

The patterns here are templates - always customize based on:

• Specific connector documentation from PowerAutomateDocs/
• Actual error details from erreur.json
• User's flow requirements and constraints