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1 minute readNewAgent-ready

MCP tools say which calls change things

Every Last Price MCP tool now carries a title and hints that tell your host whether a call only reads, changes or deletes something, or reaches outside Last Price, so it can ask you before the calls that matter.

The Tool Annotations section of the documentation in dark mode, listing the four hints and an example for delete_function

MCP hosts decide when to ask you before a tool runs. They can now tell from the tool itself.

  • Read-only means read-only: readOnlyHint is true only when a call changes nothing. A priced call such as compute_price is not read-only, because it is metered and charged.
  • Destructive is marked: overwriting settings, deleting, approving and pushing prices to your store carry destructiveHint.
  • Outside calls are marked: wallet payments, emails, card checkouts, your store and endpoints you registered carry openWorldHint.
  • A narrower set for directories: a listing can connect to the pricing and workspace tools without the wallet payment and buyer spend tools.
  • Same in the local server: the stdio MCP server adds them with LASTPRICE_TOOL_ANNOTATIONS=1.

Questions? Write to support@last-price.ai.