threads-mcp-server

threads_create_post

Publish content to Meta Threads by sending text, an optional public image URL, or a reply to an existing post. Posts go live immediately and cannot be saved as drafts.

Instructions

Publish to Threads. This is immediately public and there is no draft state — the only undo is threads_delete_post, and everyone who saw it still saw it.

An image is fetched by Threads from the URL you give, server-side, so it must be a publicly reachable http(s) URL. A local file path cannot work here.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "text": "<text>"
    },
    "name": "threads_create_post"
  }
}

Input Schema

Name	Required	Description
`text`	Yes	Threads caps text posts at 500 characters.
`user_id`	No
`image_url`	No	Public http(s) URL Threads can fetch. Not a local path.
`reply_to_id`	No	Post id to reply to.
`wait_seconds`	No	How long to let the container process. Default 30, or 60 with an image.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Sep 7, 2026

TDQS

A4.2/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It transparently warns that the post is immediately public, has no draft state, and that deletion does not undo visibility. It also explains that images are fetched server-side and must be publicly reachable HTTP(S) URLs, which is a significant implementation detail.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is compact and front-loaded with the core purpose, followed by high-impact caveats. Every sentence earns its place, covering permanence, undo, and image URL requirements without redundancy or filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a publish tool with no annotations and no output schema, the description covers the most important operational realities: public visibility, no draft state, deletion semantics, and image URL constraints. It does not explain return values or user_id, but the included context is sufficient for an agent to invoke the tool correctly in most cases.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 80%, so the schema already documents most parameters. The description adds meaningful value beyond the schema by emphasizing that image_url must be publicly reachable and that local paths will not work. This clarifies the most error-prone parameter without repeating every schema description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description begins with 'Publish to Threads,' a specific verb and resource that clearly identifies the tool's function. It also distinguishes itself from siblings by noting that the only undo is threads_delete_post, making the create-vs-delete relationship explicit.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives clear context about publishing and the absence of a draft state, but it does not explicitly say when to use this tool instead of alternatives like threads_get_my_posts or threads_delete_post. The sibling names make the distinction inferable, but no direct when-to-use or when-not-to-use guidance is provided.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server