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MCPServerConfig

Each MCP server is defined with an MCPServerConfig: 
from definable.mcp import MCPServerConfig

server = MCPServerConfig(
    name="my-server",
    transport="stdio",
    command="npx",
    args=["-y", "@modelcontextprotocol/server-filesystem", "/home"],
    connect_timeout=30.0,
    request_timeout=60.0,
)

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Connection Parameters

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name
str
required
Unique identifier for this server. Used in tool name prefixes and logs.
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transport
str
default:"stdio"
Transport type: "stdio", "sse", or "http".

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stdio Transport

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command
str
Command to launch the server process (e.g., "npx", "python", "node").
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args
List[str]
Command-line arguments for the server process.

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SSE / HTTP Transport

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url
str
Server URL for SSE or HTTP transports.
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headers
Dict[str, str]
Custom HTTP headers (e.g., authentication tokens).

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Timeouts

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connect_timeout
float
default:"30.0"
Maximum time in seconds to establish the initial connection.
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request_timeout
float
default:"60.0"
Maximum time in seconds for individual requests (tool calls, resource reads).

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Reliability

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reconnect_on_failure
bool
default:"true"
Automatically reconnect if the connection drops.
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max_reconnect_attempts
int
default:"3"
Maximum number of reconnection attempts.

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Tool Filtering

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allowed_tools
List[str]
Whitelist of tool names. Only these tools will be exposed to the agent.
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blocked_tools
List[str]
Blacklist of tool names. These tools will be hidden from the agent.
# Only expose read operations
MCPServerConfig(
    name="filesystem",
    transport="stdio",
    command="npx",
    args=["-y", "@modelcontextprotocol/server-filesystem", "/data"],
    allowed_tools=["read_file", "list_directory", "search_files"],
)

# Block dangerous operations
MCPServerConfig(
    name="filesystem",
    transport="stdio",
    command="npx",
    args=["-y", "@modelcontextprotocol/server-filesystem", "/data"],
    blocked_tools=["write_file", "delete_file", "move_file"],
)

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MCPConfig

Group multiple servers into a single configuration: 
from definable.mcp import MCPConfig, MCPServerConfig

config = MCPConfig(
    servers=[
        MCPServerConfig(name="filesystem", transport="stdio", command="npx", args=["..."]),
        MCPServerConfig(name="github", transport="stdio", command="npx", args=["..."]),
        MCPServerConfig(name="api", transport="http", url="https://mcp.example.com"),
    ],
    auto_connect=True,
    reconnect_on_failure=True,
)
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servers
List[MCPServerConfig]
required
List of server configurations.
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auto_connect
bool
default:"true"
Automatically connect to all servers on initialization.
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reconnect_on_failure
bool
default:"true"
Global reconnection setting (can be overridden per server).

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Loading from a File

Store configuration in a JSON file and load it: 
{
  "servers": [
    {
      "name": "filesystem",
      "transport": "stdio",
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "/tmp"]
    },
    {
      "name": "api",
      "transport": "http",
      "url": "https://mcp.example.com/mcp",
      "headers": {"Authorization": "Bearer token"}
    }
  ]
}

config = MCPConfig.from_file("mcp_config.json")
Save configuration back to a file: 
config.to_file("mcp_config.json")

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Managing Servers

Add or remove servers dynamically: 
config = MCPConfig(servers=[])

# Add a server
config.add_server(MCPServerConfig(name="fs", transport="stdio", command="npx", args=[...]))

# Get a specific server
server = config.get_server("fs")

# Remove a server
config.remove_server("fs")

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Transport-Specific Examples

MCPServerConfig(
    name="sqlite",
    transport="stdio",
    command="npx",
    args=["-y", "@modelcontextprotocol/server-sqlite", "database.db"],
)