meta-social-mcp

fb_create_photo_post

Publish a photo with optional caption to a Facebook Page using a publicly accessible image URL. Simplify social media posting by turning an image link into a published post.

Instructions

Publish a photo post to the Facebook Page from an image URL.

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": {
      "image_url": "<image_url>"
    },
    "name": "fb_create_photo_post"
  }
}

Input Schema

Name	Required	Description	Default
`caption`	No	Caption text for the photo.
`image_url`	Yes	Publicly reachable URL of the image.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Sep 8, 2026

TDQS

A3.5/5.0

Behavior2/5

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

With no annotations, the description carries the full burden of behavioral disclosure. It states the action and source but does not mention permissions, that the post is published immediately, failure conditions, URL reachability requirements, or any side effects beyond the obvious publish action.

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?

One direct sentence, front-loaded with the action and target, with no filler or repetition of schema details.

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

Completeness3/5

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

The tool is simple and all parameters are documented, but with no annotations or output schema, the description does not explain return values, required page context/authentication, or whether the post is immediate rather than scheduled. Basic but not fully self-sufficient.

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 coverage is 100%, so the schema already documents image_url and caption. The description adds only the notion that the image is sourced from a URL, which mirrors image_url's schema description without adding new meaning.

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 uses a specific verb ('Publish'), a clear resource ('photo post'), and the required source ('image URL'), which is enough to distinguish it from sibling tools like fb_create_text_post and fb_create_video_post.

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 wording implies this is the correct tool when publishing a photo from a URL, but it never explicitly contrasts it with fb_create_text_post, fb_create_video_post, or fb_schedule_post. An agent must infer usage from the tool name and sibling names.

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