mastodon-mcp-server

Status Post

status_post

Publish a new Mastodon post (toot) with optional media, visibility, language, content warnings, and replies.

Instructions

Post a new status (toot).

Input Schema

TableJSON Schema

Name	Required	Description	Default
`status`	No	Text content of the status (preferred argument name).
`content`	No	Backward-compatible alias for status text.
`language`	No	ISO 639-1 language code (e.g. 'en', 'cs'). If omitted, the language is auto-detected from 'status'/'content'.
`media_ids`	No	List of media attachment IDs to attach.
`sensitive`	No	Mark media as sensitive (default False).
`visibility`	No	'public', 'unlisted', 'private', or 'direct' (default 'public').	public
`spoiler_text`	No	Content warning / spoiler text shown before the status.
`in_reply_to_id`	No	Numeric ID of the status to reply to.

Output Schema

TableJSON Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed24 schema fields changedv1.0.5Sep 12, 2026

addedInput schema / additionalProperties
```
Added value: +false
```

addedInput schema / properties / content / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / content / default
```
Added value: +null
```

changedInput schema / properties / content / description

Previous value: -"Text content of the status. Supports HTML or plain text."New value: +"Backward-compatible alias for status text."

removedInput schema / properties / content / type
```
Removed value: -"string"
```

addedInput schema / properties / in_reply_to_id / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / in_reply_to_id / default
```
Added value: +null
```
removedInput schema / properties / in_reply_to_id / type
```
Removed value: -"string"
```

addedInput schema / properties / language / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / language / default
```
Added value: +null
```

changedInput schema / properties / language / description

Previous value: -"ISO 639-1 language code (e.g. 'en', 'cs')."New value: +"ISO 639-1 language code (e.g. 'en', 'cs'). If omitted, the\nlanguage is auto-detected from 'status'/'content'."

removedInput schema / properties / language / type
```
Removed value: -"string"
```

addedInput schema / properties / media_ids / anyOf

Added value: +[
+  {
+    "items": {
+      "type": "string"
+    },
+    "type": "array"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / media_ids / default
```
Added value: +null
```
removedInput schema / properties / media_ids / items
```
Removed value: -{
-  "type": "string"
-}
```
removedInput schema / properties / media_ids / type
```
Removed value: -"array"
```
addedInput schema / properties / sensitive / default
```
Added value: +false
```

addedInput schema / properties / spoiler_text / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / spoiler_text / default
```
Added value: +null
```
removedInput schema / properties / spoiler_text / type
```
Removed value: -"string"
```

addedInput schema / properties / status

Added value: +{
+  "anyOf": [
+    {
+      "type": "string"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "description": "Text content of the status (preferred argument name)."
+}

addedInput schema / properties / visibility / default
```
Added value: +"public"
```
removedInput schema / required
```
Removed value: -[
-  "content"
-]
```

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "properties": {
+    "result": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "result"
+  ],
+  "type": "object",
+  "x-fastmcp-wrap-result": true
+}

First observedv1.0.1Jun 26, 2026

TDQS

C2.9/5.0

Behavior2/5

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

Annotations already declare readOnlyHint=false, idempotentHint=false, openWorldHint=true and destructiveHint=false, so the safety profile is covered. The description adds nothing beyond that – no mention that posting is public by default, that it is non-idempotent (duplicate posts), or that it publishes to the open network. No value added over structured data.

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

Conciseness4/5

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

A single, front-loaded sentence with zero waste. It is appropriately sized, though the extreme brevity borders on under-specification rather than true conciseness.

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

Completeness2/5

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

For an 8-parameter publish/mutation tool, the description is too thin. With no output schema explanation needed, an agent still lacks confirmation about the default public visibility, the alias relationship between status and content, or the reply/thread behavior implied by in_reply_to_id.

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

Parameters3/5

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

Schema description coverage is 100%, so every parameter (status/content aliases, language, media_ids, sensitive, visibility, spoiler_text, in_reply_to_id) is fully documented in the schema. The description adds no parameter meaning, so the baseline 3 applies.

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

Purpose4/5

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

States a specific verb and resource ('Post a new status') and the parenthetical '(toot)' clarifies the Mastodon domain term. An agent can distinguish it from read-oriented siblings like status_get or status_context, though it never explicitly names which sibling to use for a reply or boost.

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

Usage Guidelines2/5

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

There is no guidance on when to use this versus alternatives such as status_reblog or status_favourite, nor any prerequisites. The agent must infer usage entirely from the tool name.

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

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