cayu.mcp definitions

Public Cayu API. Definitions are grouped by their public source module, and definitions from private implementation modules appear on their package’s page; adding a symbol does not move existing links. The import shown at each entry is a supported public namespace. Read the Python API overview and install the required extra.

`DEFAULT_MCP_CLIENT_NAME`

from cayu.mcp import DEFAULT_MCP_CLIENT_NAME

DEFAULT_MCP_CLIENT_NAME = 'cayu'

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`DEFAULT_MCP_CLIENT_VERSION`

from cayu.mcp import DEFAULT_MCP_CLIENT_VERSION

DEFAULT_MCP_CLIENT_VERSION = __version__

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`DEFAULT_MCP_CONTAINMENT_KILL_TIMEOUT_S`

from cayu.mcp import DEFAULT_MCP_CONTAINMENT_KILL_TIMEOUT_S

DEFAULT_MCP_CONTAINMENT_KILL_TIMEOUT_S = 2.0

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`DEFAULT_MCP_CONTAINMENT_STARTUP_TIMEOUT_S`

from cayu.mcp import DEFAULT_MCP_CONTAINMENT_STARTUP_TIMEOUT_S

DEFAULT_MCP_CONTAINMENT_STARTUP_TIMEOUT_S = 5.0

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`DEFAULT_MCP_CONTAINMENT_TERM_TIMEOUT_S`

from cayu.mcp import DEFAULT_MCP_CONTAINMENT_TERM_TIMEOUT_S

DEFAULT_MCP_CONTAINMENT_TERM_TIMEOUT_S = 2.0

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`DEFAULT_MCP_MAX_LIST_ITEMS`

from cayu.mcp import DEFAULT_MCP_MAX_LIST_ITEMS

DEFAULT_MCP_MAX_LIST_ITEMS = 10000

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`DEFAULT_MCP_MAX_LIST_PAGES`

from cayu.mcp import DEFAULT_MCP_MAX_LIST_PAGES

DEFAULT_MCP_MAX_LIST_PAGES = 100

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`DEFAULT_MCP_MAX_MESSAGE_BYTES`

from cayu.mcp import DEFAULT_MCP_MAX_MESSAGE_BYTES

DEFAULT_MCP_MAX_MESSAGE_BYTES = 16 * 1024 * 1024

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`DEFAULT_MCP_MAX_RESPONSE_BYTES`

from cayu.mcp import DEFAULT_MCP_MAX_RESPONSE_BYTES

DEFAULT_MCP_MAX_RESPONSE_BYTES = 64 * 1024 * 1024

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`DEFAULT_MCP_REQUEST_TIMEOUT_S`

from cayu.mcp import DEFAULT_MCP_REQUEST_TIMEOUT_S

DEFAULT_MCP_REQUEST_TIMEOUT_S = 30.0

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`MCP_MODERN_PROTOCOL_VERSION`

from cayu.mcp import MCP_MODERN_PROTOCOL_VERSION

MCP_MODERN_PROTOCOL_VERSION = '2026-07-28'

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`MCP_PROTOCOL_VERSION`

from cayu.mcp import MCP_PROTOCOL_VERSION

MCP_PROTOCOL_VERSION = '2025-06-18'

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`McpCallDeadlineExceededError`

from cayu.mcp import McpCallDeadlineExceededError

Raised when an MCP exchange exceeds its absolute deadline.

Bases: TimeoutError.

This type’s implementation and inherited behavior are available in the linked release source.

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`McpIdleTimeoutError`

from cayu.mcp import McpIdleTimeoutError

Raised when an MCP transport stops making inbound progress.

Bases: TimeoutError.

This type’s implementation and inherited behavior are available in the linked release source.

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`McpMessageTooLargeError`

from cayu.mcp import McpMessageTooLargeError

Raised when one JSON-RPC message or SSE event exceeds its byte limit.

Bases: McpProtocolError.

This type’s implementation and inherited behavior are available in the linked release source.

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`McpPeerClosedError`

from cayu.mcp import McpPeerClosedError

Raised when the peer closes before completing the expected response.

Bases: McpProtocolError.

This type’s implementation and inherited behavior are available in the linked release source.

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`McpProtocolEra`

from cayu.mcp import McpProtocolEra

MCP wire era selected once for one transport connection.

Bases: StrEnum.

Fields and attributes

Defaults below are source expressions; Field(...) includes schema/validation settings and default_factory creates a fresh value. Inherited declarations are included. Constructor behavior follows the model or dataclass shown in the bases/decorators.

Name	Type	Default
`LEGACY`	`class attribute`	`'legacy'`
`MODERN_2026_07_28`	`class attribute`	`MCP_MODERN_PROTOCOL_VERSION`

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`McpProtocolError`

from cayu.mcp import McpProtocolError

Raised when an MCP server violates the expected JSON-RPC contract.

Bases: RuntimeError.

This type’s implementation and inherited behavior are available in the linked release source.

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`McpResponseTooLargeError`

from cayu.mcp import McpResponseTooLargeError

Raised when an aggregate HTTP response exceeds its byte limit.

Bases: McpProtocolError.

This type’s implementation and inherited behavior are available in the linked release source.

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`McpTransportLimits`

from cayu.mcp import McpTransportLimits

Allocation and timing bounds for one MCP transport exchange.

Bases: BaseModel.

Fields and attributes

Name	Type	Default
`max_message_bytes`	`int`	`DEFAULT_MCP_MAX_MESSAGE_BYTES`
`max_response_bytes`	`int`	`DEFAULT_MCP_MAX_RESPONSE_BYTES`
`idle_timeout_s`	`float`	`30.0`
`total_call_timeout_s`	`float`	`30.0`

validate_byte_limit (method)

McpTransportLimits.validate_byte_limit(value: object, info) -> int

validate_timeout (method)

McpTransportLimits.validate_timeout(value: object, info) -> float

validate_response_limit (method)

McpTransportLimits.validate_response_limit() -> McpTransportLimits

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`StdioMcpProcessLifetime`

from cayu.mcp import StdioMcpProcessLifetime

Ownership policy for a local stdio MCP subprocess.

Bases: StrEnum.

Fields and attributes

Name	Type	Default
`PARENT_DEATH_CONTAINMENT`	`class attribute`	`'parent_death_containment'`
`GRACEFUL_CLEANUP`	`class attribute`	`'graceful_cleanup'`
`PERSISTENT_DETACHED`	`class attribute`	`'persistent_detached'`

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`SUPPORTED_MCP_PROTOCOL_VERSIONS`

from cayu.mcp import SUPPORTED_MCP_PROTOCOL_VERSIONS

SUPPORTED_MCP_PROTOCOL_VERSIONS = frozenset({*SUPPORTED_LEGACY_MCP_PROTOCOL_VERSIONS, MCP_MODERN_PROTOCOL_VERSION})

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