---
title: "tool si.act.mark_rival"
description: "a brand, the rival's entity, the evidence: the fact."
section: reference
address: /reference/tools/si-act-mark_rival
contract: 0476e35e6e275db5
---

# tool si.act.mark_rival

a brand, the rival's entity, the evidence: the fact.

[figure: Over MCP, si.act.mark_rival takes MarkRivalInput and returns a card whose body is RivalMarking.]

the fact. The call needs the act grant at the brand rung.



| | |
|---|---|
| input | [MarkRivalInput](/concepts/markrivalinput) |
| result | a card whose body is [RivalMarking](/concepts/rivalmarking) |
| read-only | no |
| destructive | yes |
| card address | `ui://scale-intelligence/cards/RivalMarking` |
| HTTP route | [`/v1/act/mark_rival`](/reference/act/mark_rival) |





| field | type | required | note |
|---|---|---|---|
| `brand` | `id` | yes |  |
| `rival` | `id` | yes |  |
| `evidence` | [EvidenceRef](/concepts/evidenceref) | yes |  |