Function buildSchemaNotSentHint

src/services/tools/toolExecution.ts:578–597

(
  tool: Tool,
  messages: Message[],
  tools: readonly { name: string }[],
)

 * model to re-load the tool; this hint does. Null if the schema was sent.
 */
export function buildSchemaNotSentHint(
  tool: Tool,
  messages: Message[],
  tools: readonly { name: string }[],
): string | null {
  // Optimistic gating — reconstructing claude.ts's full useToolSearch
  // computation is fragile. These two gates prevent pointing at a ToolSearch
  // that isn't callable; occasional misfires (Haiku, tst-auto below threshold)
  // cost one extra round-trip on an already-failing path.
  if (!isToolSearchEnabledOptimistic()) return null
  if (!isToolSearchToolAvailable(tools)) return null
  if (!isDeferredTool(tool)) return null
  const discovered = extractDiscoveredToolNames(messages)
  if (discovered.has(tool.name)) return null
  return (
    `\n\nThis tool's schema was not sent to the API — it was not in the discovered-tool set derived from message history. ` +
    `Without the schema in your prompt, typed parameters (arrays, numbers, booleans) get emitted as strings and the client-side parser rejects them. ` +
    `Load the tool first: call ${TOOL_SEARCH_TOOL_NAME} with query "select:${tool.name}", then retry this call.`
  )
}

async function checkPermissionsAndCallTool(
  tool: Tool,