⚠️ Solace Agent Mesh plugins in Python are now deprecated

👋 Thank you to everyone who's used the Solace Agent Mesh plugins! This Python version is now deprecated — it's no longer under active development and won't receive new features, bug fixes or security updates.

🚀 Check out the new version of Solace Agent Mesh → https://docs.solace.com/Agent-Mesh/agent-mesh.htm

🖥️ A free edition of the Solace Agent Mesh desktop app is available: https://solace.com/products/agent-mesh/download

These packages remain installable; the repository will be archived (read-only) for reference.

SQL Database Tool Plugin

This plugin for Solace Agent Mesh (SAM) provides a powerful and dynamic tool for executing SQL queries against a database. It allows any agent to be augmented with direct database access.

Unlike the sam-sql-database agent, which provides a complete Natural-Language-to-SQL agent, this plugin provides a tool that can be added to any existing or new agent. This allows you to create multi-faceted agents that can interact directly with databases for specific, targeted tasks.

About Solace Agent Mesh

Solace Agent Mesh (SAM) is an open-source framework for building event-driven, multi-agent AI systems where specialized agents collaborate on complex tasks. It provides a standardized way for agents to communicate, share data, and integrate with external systems while keeping components loosely coupled and production-ready.

SAM helps you:

• Build event-driven multi-agent systems on Solace Event Mesh
• Connect agents, tools, gateways, and services through a common runtime
• Extend projects with installable plugins such as sam-sql-database-tool

Learn more in the Solace Agent Mesh documentation and the main project repository.

Key Features

• Dynamic Tool Creation: Define custom SQL query tools directly in your agent's YAML configuration. Each tool instance is completely independent.
• Multi-Database Support: Natively supports PostgreSQL, MySQL, MariaDB, MSSQL, and Oracle.
• Dedicated Connections: Each tool instance creates its own dedicated database connection, allowing for fine-grained configuration.
• Flexible Schema Handling:
  • Automatic schema detection and summarization for LLM prompting.
  • Manual override for providing a detailed schema and a natural language summary.

Installation

To add this tool to a new or existing agent, you must first install it and then manually add the tool configuration to your agent's YAML file:

sam plugin install sam-sql-database-tool

This creates a new component configuration at configs/plugins/<your-component-name-kebab-case>.yaml.

Configuration

To use the tool, add one or more tool_type: python blocks to the tools list in your agent's app_config. Each block will create a new, independent tool instance.

Example Tool Configuration

Here is an example of configuring a tool to query a customer database.

# In your agent's app_config:
tools:
  - tool_type: python
    component_module: "sam_sql_database_tool.tools"
    class_name: "SqlDatabaseTool"
    tool_config:
      # --- Tool Definition for LLM ---
      tool_name: "QueryCustomerDatabase"
      tool_description: "Executes a SQL query against the customer database."

      # --- Database Connection Configuration ---
      connection_string: "${CUSTOMER_DB_CONNECTION_STRING}"

      # --- Schema Handling ---
      auto_detect_schema: true
      # schema_summary_override: "A table named 'customers' with columns 'id' and 'name'."
      # max_enum_cardinality: 100
      # schema_sample_size: 100
      # cache_ttl_seconds: 3600

      # --- Table Filtering (glob patterns supported: *, ?, [seq]) ---
      # include_tables:            # Only include matching tables in schema detection
      #   - "customers*"
      #   - "orders*"
      # exclude_tables:            # Exclude matching tables from schema detection
      #   - "bkp_*"
      #   - "*_temp"

      # --- Connection Pool (optional tuning) ---
      # pool_size: 10
      # max_overflow: 10
      # pool_timeout: 30
      # pool_recycle: 1800      # Set below your DB's idle timeout
      # pool_pre_ping: true

      # --- Engine Settings (optional) ---
      # echo: false             # Log all SQL statements (development only)
      # isolation_level: "READ_COMMITTED"
      # connect_args: {}        # Extra driver kwargs, e.g. {sslmode: "require"}

tool_config Details

• tool_name: (Required) The function name the LLM will use to call the tool.

• tool_description: (Optional) A clear description for the LLM explaining what the tool does.

• connection_string: (Required) The full database connection string. It is highly recommended to use a single environment variable for the entire string. Supported formats:

  • PostgreSQL: postgresql+psycopg2://user:password@host:port/dbname
  • MySQL: mysql+pymysql://user:password@host:port/dbname
  • MariaDB: mysql+pymysql://user:password@host:port/dbname
  • MSSQL (Microsoft ODBC - Recommended): mssql+pyodbc://user:password@host:port/dbname?driver=ODBC+Driver+18+for+SQL+Server
    • Official Microsoft driver with full feature support (Azure AD auth, Always Encrypted, etc.).
    • Requires ODBC Driver 17 or 18 installed on the host system.
    • Driver 18+ enables encryption by default. Control this with the Encrypt parameter:
      • Encrypt=yes / Encrypt=mandatory — encrypt all traffic (default in Driver 18+).
      • Encrypt=no / Encrypt=optional — disable encryption.
      • Encrypt=strict — strict TLS; ignores TrustServerCertificate and requires a fully valid certificate chain (Driver 18+ only).
    • Use TrustServerCertificate=yes to bypass certificate validation for self-signed certificates (not applicable when Encrypt=strict).
    • See the Microsoft docs on ODBC connection string keywords for the full list of supported parameters.
  • MSSQL (FreeTDS): mssql+pyodbc://user:password@host:port/dbname?driver=FreeTDS
    • Open-source driver with simpler installation: sudo apt-get install freetds-dev freetds-bin tdsodbc && sudo odbcinst -i -d -f /usr/share/tdsodbc/odbcinst.ini
    • Works well for standard SQL operations.
  • Oracle: oracle+oracledb://user:password@host:port/?service_name=SERVICE_NAME
    • Uses the oracledb driver in thin mode (no Oracle Instant Client required).
    • Replace SERVICE_NAME with your Oracle service name (e.g., XEPDB1, ORCL).

• auto_detect_schema: (Optional, default: true) If true, the plugin attempts to automatically detect the database schema. If false, you must provide schema_summary_override.

• schema_summary_override: (Required if auto_detect_schema is false) A concise natural language summary of the schema, suitable for direct inclusion in an LLM prompt.

• max_enum_cardinality: (Optional, default: 100) Maximum number of distinct values to consider a column as an enum. Increase for columns like countries (190+), decrease for faster init times.

• schema_sample_size: (Optional, default: 100) Number of rows to sample per table for schema detection. Increase for better accuracy on sparse data, decrease for faster init times.

• cache_ttl_seconds: (Optional, default: 3600) Time-to-live for schema cache in seconds. After this duration, the schema will be re-detected on the next query. Set to 0 to disable caching.

• include_tables: (Optional) A list of glob patterns for tables to include in schema detection. If set, only tables matching at least one pattern are included. Supports wildcards: *, ?, [seq]. Example: ["tms_trx*", "tms_alert*"].

• exclude_tables: (Optional) A list of glob patterns for tables to exclude from schema detection. Applied after include_tables. Supports the same wildcard syntax. Example: ["bkp_*", "*_temp", "*_dev"]. Both options can be used together and matching is case-sensitive.

  Important: Table filtering is not access control. These options only control which tables appear in the schema provided to the LLM. They do not prevent the LLM from executing queries against other tables in the database — for example, by querying database metadata or being prompted to access tables outside the filter. The underlying database connection still has full access to all tables the database user can see.

  To reduce the likelihood of the LLM querying unfiltered tables, add an instruction to your agent such as:

  Only query tables that appear in your tool's schema description.
  Do not query database metadata tables or any tables not listed in your schema.
  

  For actual access control, configure the database user in the connection string with SELECT permissions restricted to only the allowed tables. This is the only way to guarantee that the LLM cannot access tables outside the intended scope.

Connection Pool Settings

• pool_size: (Optional, default: 10) Number of persistent connections to maintain in the pool. Increase for high-concurrency workloads; decrease to reduce resource usage on low-traffic deployments.
• max_overflow: (Optional, default: 10) Maximum number of additional temporary connections allowed beyond pool_size during traffic spikes. The total connection limit is pool_size + max_overflow.
• pool_timeout: (Optional, default: 30) Seconds to wait for a free connection from the pool before raising a TimeoutError. Increase if you frequently hit timeouts under load.
• pool_recycle: (Optional, default: 1800) Recycle connections after this many seconds to prevent "lost connection" errors. Set this value below your database server's idle connection timeout. Use -1 to disable recycling.
• pool_pre_ping: (Optional, default: true) Test each connection for liveness before use. Keeps the pool healthy after network interruptions. Disable only to reduce per-query latency on very reliable networks.

Engine Settings

• echo: (Optional, default: false) Log all SQL statements to the Python logger (sqlalchemy.engine). Enable for development and troubleshooting only — do not use in production.
• isolation_level: (Optional) Set the transaction isolation level for all connections. Accepted values depend on the database dialect — common values are READ_COMMITTED, REPEATABLE_READ, SERIALIZABLE, and AUTOCOMMIT. Omit to use the database's default.
• connect_args: (Optional, default: {}) A dictionary of extra keyword arguments passed directly to the database driver's connect() call. Use this for driver-specific options such as SSL certificates, connection timeouts, or character set settings. Example for PostgreSQL: connect_args: {sslmode: "require"}.

Tool Parameters

The generated tool accepts a single parameter:

• query (string, required): The SQL query to execute.