Result of a tool call, returned by the harness's onToolCall.
content is whatever string representation of the result the model
should see next turn. Convention: stringify objects, prefer one-line
for primitives. isError tells the model the call failed (Anthropic
surfaces this as is_error: true in the next turn's tool_result
block; other providers handle similarly).
Result of a tool call, returned by the harness's
onToolCall.contentis whatever string representation of the result the model should see next turn. Convention: stringify objects, prefer one-line for primitives.isErrortells the model the call failed (Anthropic surfaces this asis_error: truein the next turn'stool_resultblock; other providers handle similarly).