---
title: "tool si.act.place_participant"
description: "Places one party in one role on one stock of a vertical's chain, with the evidence for it: The answer gives the participant, ready or not ready with the reason."
section: reference
address: /reference/tools/si-act-place_participant
contract: 0476e35e6e275db5
---

# tool si.act.place_participant

Places one party in one role on one stock of a vertical's chain, with the evidence for it: The answer gives the participant, ready or not ready with the reason.

[figure: Over MCP, si.act.place_participant takes PlaceParticipantInput and returns a card whose body is MarketParticipant.]

The answer gives the participant, ready or not ready with the reason. The call needs the act grant at the brand rung.



| | |
|---|---|
| input | [PlaceParticipantInput](/concepts/placeparticipantinput) |
| result | a card whose body is [MarketParticipant](/concepts/marketparticipant) |
| read-only | no |
| destructive | yes |
| card address | `ui://scale-intelligence/cards/MarketParticipant` |
| HTTP route | [`/v1/act/place_participant`](/reference/act/place_participant) |





| field | type | required | note |
|---|---|---|---|
| `vertical` | `id` | yes |  |
| `segment` | `id` | no |  |
| `stock` | `text` | yes |  |
| `party` | `id` | yes |  |
| `party_kind` | `one of company \| brand \| person \| account \| community \| organisation` | yes |  |
| `role` | [RoleAroundADecision](/concepts/rolearoundadecision) | yes |  |
| `side` | `one of demand \| supply \| intermediary \| influence \| rules` | yes |  |
| `impact_on` | [ParticipantImpact](/concepts/participantimpact) | no |  |
| `evidence` | [EvidenceRef](/concepts/evidenceref) | yes |  |