mcp-typescript-sdk-type--calling-client-calltool-returns-content-typed-as-u-ae9b5ee3

THEN Upgrade to the latest version of @modelcontextprotocol/typescript-sdk which correctly types content as an array of content block objects. For older versions, cast the result explicitly, e.g., const ret = (await client.callTool(...)) as { content: Array<{type: string; text?: string}> };

// Before fix (incorrect typing):
const ret = await client.callTool({ name: 'a' });
// ret.content is unknown — TypeScript error on next line:
if (ret.content.length && ret.content[0].type === 'text') {}

// Workaround (type assertion):
const ret = (await client.callTool({ name: 'a' })) as { content: Array<{type: string; text: string}> };