MCP Tools Reference: bigquerymigration.googleapis.com

Tool: generate_ddl_suggestion

Suggests Data Definition Language (DDL) statements for an input query. For example, CREATE TABLE or CREATE VIEW. The generated DDL provides schema definitions for tables and views that are used in the query. To get DDL suggestions, call this tool, and then use the fetch_ddl_suggestion tool with the returned suggestion ID to retrieve the DDL. You can then prepend the retrieved DDL to the original input query and translate it again to improve translation quality.

The following code sample shows how to use curl to call the generate_ddl_suggestion MCP tool.

Curl Request 
curl --location 'https://bigquerymigration.googleapis.com/mcp' \
--header 'content-type: application/json' \
--header 'accept: application/json, text/event-stream' \
--data '{
  "method": "tools/call",
  "params": {
    "name": "generate_ddl_suggestion",
    "arguments": {
      // provide these details according to the tool's MCP specification
    }
  },
  "jsonrpc": "2.0",
  "id": 1
}'

Input Schema

Request message for GenerateDdlSuggestion.

GenerateDdlSuggestionRequest

JSON representation 
{
  "projectNumber": string,
  "location": string,
  "inputQuery": string,
  "sourceDialect": string,
  "targetDialect": string
}
Fields
projectNumber

string

Required. The Google Cloud project number.
location

string

Required. The location.
inputQuery

string

Required. The query string for which the DDL suggestion is generated.
sourceDialect

string

Required. The dialect of the source query. The following source to target dialect pairs are supported: source: Teradata, Bteq, Redshift, Oracle, HiveQL, Impala, SparkSQL, Snowflake, Netezza, AzureSynapse, Vertica, SQLServer, Presto, MySQL, Postgresql, Db2, SQLite, Greenplum, BigQuery; target: BigQuery.

targetDialect

string

Required. The dialect of the target query. See list of supported pairs in source_dialect.

Output Schema

Response message for GenerateDdlSuggestion.

GenerateDdlSuggestionResponse

JSON representation 
{
  "suggestion": string,
  "suggestionState": string,
  "logs": [
    {
      object (Log)
    }
  ],
  "errorInfo": {
    object (ErrorInfo)
  }
}
Fields
suggestion

string

The ID of the DDL suggestion. Use this ID for the suggestion field in fetch_ddl_suggestion tool.
suggestionState

string

The current state of the DDL suggestion, for example, RUNNING, SUCCEEDED or FAILED.
logs[]

object (Log)

A list of logs generated during the DDL suggestion process.
errorInfo

object (ErrorInfo)

The error information.

Log

JSON representation 
{
  "severity": string,
  "category": string,
  "message": string,
  "action": string,
  "effect": string,
  "impactedObject": string
}
Fields
severity

string

Severity of the translation record, for example, INFO, WARNING, or ERROR.
category

string

Category of the error or warning, for example, SyntaxError.
message

string

Detailed message of the record.
action

string

Recommended action to address the log.
effect

string

The effect or impact of the issue noted in the log. Effect can be one of the following values: CORRECTNESS: Errors with this effect indicate that the translation service couldn't meaningfully process the translation. This is caused by issues in the user's input such as incorrect language or formatting, or using an unsupported file type. COMPLETENESS: Errors with this effect indicate that the translation service doesn't have sufficient information to complete the translation. This can be caused by missing information in the user's input such as missing metadata for name resolution. COMPATIBILITY: Errors with this effect indicate that the translation service encountered compatibility issues when it processed the translation. This can happen when the target platform doesn't support a feature used in the input script, and the translation service tries to make a semantic approximation for the target platform. NONE: Errors with this effect are purely informational messages that have no effect on the output. Effects are ordered by their stage in the translation process. For example, CORRECTNESS issues are identified before COMPLETENESS issues.
impactedObject

string

Name of the object that is impacted by the log message.

ErrorInfo

JSON representation 
{
  "reason": string,
  "domain": string,
  "metadata": {
    string: string,
    ...
  }
}
Fields
reason

string

The reason for the error. This is a constant value that identifies the proximate cause of the error. Error reasons are unique within a particular domain of errors. This should be at most 63 characters and match a regular expression of [A-Z][A-Z0-9_]+[A-Z0-9], which represents UPPER_SNAKE_CASE.
domain

string

The logical grouping to which the "reason" belongs. The error domain is typically the registered service name of the tool or product that generates the error. Example: "pubsub.googleapis.com". If the error is generated by some common infrastructure, the error domain must be a globally unique value that identifies the infrastructure. For Google API infrastructure, the error domain is "googleapis.com".
metadata

map (key: string, value: string)

Additional structured details about this error.

Keys must match a regular expression of [a-z][a-zA-Z0-9-_]+ but should ideally be lowerCamelCase. Also, they must be limited to 64 characters in length. When identifying the current value of an exceeded limit, the units should be contained in the key, not the value. For example, rather than {"instanceLimit": "100/request"}, should be returned as, {"instanceLimitPerRequest": "100"}, if the client exceeds the number of instances that can be created in a single (batch) request.

An object containing a list of "key": value pairs. Example: { "name": "wrench", "mass": "1.3kg", "count": "3" }.

MetadataEntry

JSON representation 
{
  "key": string,
  "value": string
}
Fields
key

string
value

string

Tool Annotations

Tool annotations are sent to MCP clients to describe the basic risk of a given tool. Most clients treat these hints as untrusted, but they can be used to decide when a confirmation prompt might be sent to a user.

Along with the title string, the following boolean hints are defined as follows:

  • readOnlyHint: If true, the tool doesn't modify its environment. Default: false.
  • destructiveHint: If true, then the tool can perform destructive actions. If false, then the tool can only perform additive actions. Default: true.
  • idempotentHint: If true, then calling the tool repeatedly with the same arguments will have no additional effect on its environment. Default: false.
  • openWorldHint: If true, then the tool can interact with an 'open world' of external entities. If false, then the tool can only interact with internal entities. For example, a web search tool would be open world, while a memory tool would not be open world.

Destructive Hint: ❌ | Idempotent Hint: ❌ | Read Only Hint: ❌ | Open World Hint: ❌