Function: mergeAgentTools()

Call Signature

function mergeAgentTools<TServerTools>(serverTools, clientTools): TServerTools;

Merge a server-side tool array with the AG-UI client-declared tools received in the request body.

Rules:

Server tools win on name collision. The client's declaration is ignored if the server already has a tool with that name. The client's UI-side handler still fires when the streamed tool-result event comes through (see chat-client.ts onToolCall), giving the "after server execution the client also handles" semantic for free.
Client-only tools (name not in serverTools) become no-execute entries: the runtime's existing ClientToolRequest path handles them — server emits a tool-call request, client executes via its registered handler, client posts back the result.

Typing:

Empty clientTools preserves the server tuple (closed name union).
Non-empty clientTools returns a widened array that honestly includes client stubs, so the merged array does not claim a closed server-only name union.

TServerTools extends readonly AnyTool[]

TServerTools

The server's tool array (e.g. from [myToolDef.server(...)]). Pass directly to chat({ tools }).

readonly []

The tools array received from chatParamsFromRequest(...) / chatParamsFromRequestBody(...).

TServerTools

A merged array suitable for chat({ tools }).

function mergeAgentTools<TServerTools>(serverTools, clientTools): MergedAgentTools<TServerTools>;

Merge a server-side tool array with the AG-UI client-declared tools received in the request body.

Rules:

Server tools win on name collision. The client's declaration is ignored if the server already has a tool with that name. The client's UI-side handler still fires when the streamed tool-result event comes through (see chat-client.ts onToolCall), giving the "after server execution the client also handles" semantic for free.
Client-only tools (name not in serverTools) become no-execute entries: the runtime's existing ClientToolRequest path handles them — server emits a tool-call request, client executes via its registered handler, client posts back the result.

Typing:

Empty clientTools preserves the server tuple (closed name union).
Non-empty clientTools returns a widened array that honestly includes client stubs, so the merged array does not claim a closed server-only name union.