# MCP tool reference 1 callable tools. Use tools/call at https://mcp.schedulerzero.com/mcp with the exact tool name and arguments below. The /tools/ paths in this view are documentation identifiers, not HTTP endpoints. Request execution is disabled for this reference. Inputs are shown for personal API keys (bound) and for OAuth/delegated agents. Output schemas describe MCP structuredContent: native objects pass through; arrays, scalars and null use a data wrapper. Text content retains the native JSON result. [Connect a client](/mcp/connect) · [Authentication and authorization](/authentication) · [Generated auth guide](/auth.md) · [Download tool catalog](/mcp-catalog.json) · [Agent documentation](/llms.txt) ## manage_custom_fields List, create, update, or delete the custom lead fields a workspace collects. Use to inspect or extend the workspace's lead schema before imports or enrichment rely on a field. Reserved lead property names are rejected; deleting a field drops its stored values. Obtain the user's explicit authorization before invoking a write or destructive action. This is a client interaction requirement, not a server-issued approval token. Scopes: workspace:read, workspace:update Risk: write; confirmation: explicit; idempotency: supported. ### Input schema (personal API key) ```json { "type": "object", "anyOf": [ { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "list" ] } ] }, "search": { "$ref": "#/$defs/ShortText" }, "cursor": { "$ref": "#/$defs/Cursor" }, "limit": { "type": "integer", "minimum": 1, "maximum": 100 } }, "required": [ "workspaceId", "action" ], "patternProperties": { "^(?!(?:workspaceId|action|search|cursor|limit)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "workspaceId", "action", "search", "cursor", "limit" ] } }, { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "create" ] } ] }, "input": { "type": "object", "properties": { "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] } }, "required": [ "name" ], "patternProperties": { "^(?!(?:name|fieldType|defaultValue)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "name", "fieldType", "defaultValue" ] } } }, "required": [ "workspaceId", "action", "input" ], "patternProperties": { "^(?!(?:workspaceId|action|input)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "workspaceId", "action", "input" ] } }, { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "update" ] } ] }, "customFieldId": { "type": "string", "minLength": 1, "maxLength": 64 }, "input": { "type": "object", "properties": { "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] } }, "patternProperties": { "^(?!(?:name|fieldType|defaultValue)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "name", "fieldType", "defaultValue" ] }, "minProperties": 1, "maxProperties": 3 } }, "required": [ "workspaceId", "action", "customFieldId", "input" ], "patternProperties": { "^(?!(?:workspaceId|action|customFieldId|input)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "workspaceId", "action", "customFieldId", "input" ] } }, { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "delete" ] } ] }, "customFieldId": { "type": "string", "minLength": 1, "maxLength": 64 } }, "required": [ "workspaceId", "action", "customFieldId" ], "patternProperties": { "^(?!(?:workspaceId|action|customFieldId)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "workspaceId", "action", "customFieldId" ] } } ], "$defs": { "ShortText": { "type": "string", "minLength": 1, "maxLength": 256 }, "Cursor": { "type": "string", "minLength": 1, "maxLength": 2048 }, "CustomFieldName": { "type": "string", "minLength": 1, "maxLength": 64, "pattern": "^[a-z][a-z0-9_]*$" } } } ``` ### Input schema (OAuth / delegated agent) ```json { "type": "object", "properties": { "workspaceId": { "type": "string", "format": "uuid", "description": "Target Workspace UUID. Call list_workspaces to enumerate the Workspaces this credential may access, then pass the chosen id here." } }, "required": [ "workspaceId" ], "anyOf": [ { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "list" ] } ] }, "search": { "$ref": "#/$defs/ShortText" }, "cursor": { "$ref": "#/$defs/Cursor" }, "limit": { "type": "integer", "minimum": 1, "maximum": 100 } }, "required": [ "workspaceId", "action" ], "patternProperties": { "^(?!(?:workspaceId)$)[\\s\\S]*?(?:^(?!(?:workspaceId|action|search|cursor|limit)$)[\\s\\S]*$)": false }, "additionalProperties": true, "propertyNames": { "anyOf": [ { "type": "string", "enum": [ "workspaceId", "action", "search", "cursor", "limit" ] }, { "enum": [ "workspaceId" ] } ] } }, { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "create" ] } ] }, "input": { "type": "object", "properties": { "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] } }, "required": [ "name" ], "patternProperties": { "^(?!(?:name|fieldType|defaultValue)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "name", "fieldType", "defaultValue" ] } } }, "required": [ "workspaceId", "action", "input" ], "patternProperties": { "^(?!(?:workspaceId)$)[\\s\\S]*?(?:^(?!(?:workspaceId|action|input)$)[\\s\\S]*$)": false }, "additionalProperties": true, "propertyNames": { "anyOf": [ { "type": "string", "enum": [ "workspaceId", "action", "input" ] }, { "enum": [ "workspaceId" ] } ] } }, { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "update" ] } ] }, "customFieldId": { "type": "string", "minLength": 1, "maxLength": 64 }, "input": { "type": "object", "properties": { "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] } }, "patternProperties": { "^(?!(?:name|fieldType|defaultValue)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "name", "fieldType", "defaultValue" ] }, "minProperties": 1, "maxProperties": 3 } }, "required": [ "workspaceId", "action", "customFieldId", "input" ], "patternProperties": { "^(?!(?:workspaceId)$)[\\s\\S]*?(?:^(?!(?:workspaceId|action|customFieldId|input)$)[\\s\\S]*$)": false }, "additionalProperties": true, "propertyNames": { "anyOf": [ { "type": "string", "enum": [ "workspaceId", "action", "customFieldId", "input" ] }, { "enum": [ "workspaceId" ] } ] } }, { "type": "object", "properties": { "workspaceId": { "type": "string", "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|[fF]{8}-[fF]{4}-[fF]{4}-[fF]{4}-[fF]{12})$", "format": "uuid" }, "action": { "anyOf": [ { "type": "string", "enum": [ "delete" ] } ] }, "customFieldId": { "type": "string", "minLength": 1, "maxLength": 64 } }, "required": [ "workspaceId", "action", "customFieldId" ], "patternProperties": { "^(?!(?:workspaceId)$)[\\s\\S]*?(?:^(?!(?:workspaceId|action|customFieldId)$)[\\s\\S]*$)": false }, "additionalProperties": true, "propertyNames": { "anyOf": [ { "type": "string", "enum": [ "workspaceId", "action", "customFieldId" ] }, { "enum": [ "workspaceId" ] } ] } } ], "$defs": { "ShortText": { "type": "string", "minLength": 1, "maxLength": 256 }, "Cursor": { "type": "string", "minLength": 1, "maxLength": 2048 }, "CustomFieldName": { "type": "string", "minLength": 1, "maxLength": 64, "pattern": "^[a-z][a-z0-9_]*$" } } } ``` ### Output schema (structuredContent) ```json { "$defs": { "CustomFieldName": { "type": "string", "minLength": 1, "maxLength": 64, "pattern": "^[a-z][a-z0-9_]*$" }, "UtcDateTimeEncoded": { "type": "string", "pattern": "^\\d{4}-\\d{2}-\\d{2}T\\d{2}:\\d{2}:\\d{2}\\.\\d{3}Z$" }, "Cursor": { "type": "string", "minLength": 1, "maxLength": 2048 } }, "type": "object", "anyOf": [ { "allOf": [ { "anyOf": [ { "type": "object", "properties": { "items": { "type": "array", "items": { "type": "object", "properties": { "id": { "type": "string", "minLength": 1, "maxLength": 64 }, "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] }, "createdAt": { "$ref": "#/$defs/UtcDateTimeEncoded" }, "updatedAt": { "$ref": "#/$defs/UtcDateTimeEncoded" } }, "required": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ], "patternProperties": { "^(?!(?:id|name|fieldType|defaultValue|createdAt|updatedAt)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ] } } }, "nextCursor": { "anyOf": [ { "$ref": "#/$defs/Cursor" }, { "type": "null" } ] } }, "required": [ "items", "nextCursor" ], "patternProperties": { "^(?!(?:items|nextCursor)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "items", "nextCursor" ] } }, { "type": "object", "properties": { "id": { "type": "string", "minLength": 1, "maxLength": 64 }, "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] }, "createdAt": { "$ref": "#/$defs/UtcDateTimeEncoded" }, "updatedAt": { "$ref": "#/$defs/UtcDateTimeEncoded" } }, "required": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ], "patternProperties": { "^(?!(?:id|name|fieldType|defaultValue|createdAt|updatedAt)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ] } }, { "type": "object", "properties": { "deleted": { "anyOf": [ { "type": "boolean", "enum": [ true ] } ] } }, "required": [ "deleted" ], "patternProperties": { "^(?!(?:deleted)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "anyOf": [ { "type": "string", "enum": [ "deleted" ] } ] } } ] }, { "type": "object" } ] }, { "type": "object", "properties": { "data": { "allOf": [ { "anyOf": [ { "type": "object", "properties": { "items": { "type": "array", "items": { "type": "object", "properties": { "id": { "type": "string", "minLength": 1, "maxLength": 64 }, "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] }, "createdAt": { "$ref": "#/$defs/UtcDateTimeEncoded" }, "updatedAt": { "$ref": "#/$defs/UtcDateTimeEncoded" } }, "required": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ], "patternProperties": { "^(?!(?:id|name|fieldType|defaultValue|createdAt|updatedAt)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ] } } }, "nextCursor": { "anyOf": [ { "$ref": "#/$defs/Cursor" }, { "type": "null" } ] } }, "required": [ "items", "nextCursor" ], "patternProperties": { "^(?!(?:items|nextCursor)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "items", "nextCursor" ] } }, { "type": "object", "properties": { "id": { "type": "string", "minLength": 1, "maxLength": 64 }, "name": { "$ref": "#/$defs/CustomFieldName" }, "fieldType": { "type": "string", "enum": [ "text", "number", "date", "boolean", "url" ] }, "defaultValue": { "anyOf": [ { "type": "string", "maxLength": 1000 }, { "type": "null" } ] }, "createdAt": { "$ref": "#/$defs/UtcDateTimeEncoded" }, "updatedAt": { "$ref": "#/$defs/UtcDateTimeEncoded" } }, "required": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ], "patternProperties": { "^(?!(?:id|name|fieldType|defaultValue|createdAt|updatedAt)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "type": "string", "enum": [ "id", "name", "fieldType", "defaultValue", "createdAt", "updatedAt" ] } }, { "type": "object", "properties": { "deleted": { "anyOf": [ { "type": "boolean", "enum": [ true ] } ] } }, "required": [ "deleted" ], "patternProperties": { "^(?!(?:deleted)$)[\\s\\S]*$": false }, "additionalProperties": true, "propertyNames": { "anyOf": [ { "type": "string", "enum": [ "deleted" ] } ] } } ] }, { "not": { "type": "object" } } ] } }, "required": [ "data" ], "additionalProperties": false } ] } ``` ### Underlying API operations - `customFields.list`: `GET /v1/workspaces/:workspaceId/settings/custom-fields` - `customFields.create`: `POST /v1/workspaces/:workspaceId/settings/custom-fields` - `customFields.update`: `PATCH /v1/workspaces/:workspaceId/settings/custom-fields/:customFieldId` - `customFields.delete`: `DELETE /v1/workspaces/:workspaceId/settings/custom-fields/:customFieldId`