Forward extra kwargs in McpServer.call_tool override#426
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The override `McpServer.call_tool(self, tool_name, arguments)` drops kwargs
that newer versions of `openai-agents` pass to the parent. When the agents
SDK at `agents/mcp/util.py` resolves a non-None `merged_meta`, it calls
`server.call_tool(tool.name, json_data, meta=merged_meta)`, which fails:
TypeError: McpServer.call_tool() got an unexpected keyword argument 'meta'
This breaks all MCP tool calls (system.ai UC functions, Genie spaces,
Vector Search, custom Apps-hosted MCP servers) for users on a recent
`openai-agents` whenever the meta-passing branch is taken.
Forward `**kwargs` to the parent so the override stays compatible with both
old and new SDK signatures: empty kwargs forward as no-ops to old parents,
and `meta` (or any future additions) reach new parents intact.
Co-authored-by: Isaac
Signed-off-by: Bryan Qiu <bryan.qiu@databricks.com>
Co-authored-by: Isaac Signed-off-by: Bryan Qiu <bryan.qiu@databricks.com>
annzhang-db
approved these changes
May 8, 2026
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The override
McpServer.call_tool(self, tool_name, arguments)drops kwargs that newer versions ofopenai-agentspass to the parent. When the agents SDK atagents/mcp/util.pyresolves a non-Nonemerged_meta, it callsserver.call_tool(tool.name, json_data, meta=merged_meta), which fails:This breaks all MCP tool calls (system.ai UC functions, Genie spaces, Vector Search, custom Apps-hosted MCP servers) for users on a recent
openai-agentswhenever the meta-passing branch is taken.Forward
**kwargsto the parent so the override stays compatible with both old and new SDK signatures: empty kwargs forward as no-ops to old parents, andmeta(or any future additions) reach new parents intact.Co-authored-by: Isaac