preview_opinion

Checks the speaking rules and returns the summary to confirm before publishing, plus the confirm_token publish_opinion needs. Scope: write · Annotations: readOnlyHint REST equivalent: POST /open/v1/topics/{id}/opinion-preview

Only users who hold a position on the topic may publish an opinion on it — an opinion is a stated side, not a comment. This tool charges nothing and counts against the read window only.

Parameters

Name	Type	Required	Default	Notes
`topic_id`	string (uuid)	✅	—	A topic the key owner holds a position on
`content`	string	✅	—	1–500 characters
`reply_to_opinion_id`	string (uuid)		—	Omit for a top-level opinion
`language`	see languages		`en`

Returns

side_option_label is the side the opinion will be attributed to. It is resolved server-side from the owner’s position — never declared by the caller and never inferred from the text. Captured live:

{
  "can_publish": true,
  "summary": {
    "topic_title": "Will the Fed cut rates at the November 2026 meeting?",
    "fee_coins": "0.0000",
    "balance_after": "4900.0000",
    "side_option_label": "Yes",
    "content_preview": "Core PCE has cooled for three straight prints and the labour market is loosening — a November cut looks more likely than the curve implies.",
    "reply_to": null
  },
  "confirm_token": "oc1.eyJhIjoicHVibGlzaF9vcGlu…wGYcm8YxqCaKlzpg",
  "expires_at": "2026-09-08T23:39:28.246467Z"
}

fee_coins is currently "0.0000" — publishing an opinion is free today. Read the field rather than assuming; it exists so a future price change does not break agents.

Show the summary to the user and get their explicit confirmation before calling the execute tool. The token is what proves a preview happened — it is not a substitute for asking.

When publishing isn’t allowed

`reason`	Meaning
`TOPIC_CLOSED`	Not active, past `close_time`, or taken down (checked first)
`NO_POSITION`	The owner holds no position on this topic
`CONTENT_INVALID`	Empty, or over 500 characters

A reply_to_opinion_id that doesn’t exist returns OPINION_NOT_FOUND (404).

Example prompts

“Post my take on this market: …”
“Reply to that opinion saying I disagree because …”

publish_opinion · list_topic_opinions · list_my_opinions

Getting Started

MCP Server

Platform

Parameters

Returns

When publishing isn’t allowed

Example prompts

​Parameters

​Returns

​When publishing isn’t allowed

​Example prompts

​Related

Parameters

Returns

When publishing isn’t allowed

Example prompts

Related