Post

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

Adds real behavioral context beyond the annotations: it consumes paid API credits, requires confirm=true, is a read-like POST that does not publish to social platforms, and warns that reel view_count may be null or lower than the profile badge. This resolves the apparent tension of readOnlyHint=false with the POST verb. It does not address caching/rate-limit behavior (though the schema covers caching).

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

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

Front-loaded with the core purpose and return fields, but the middle is dense with reel-badge caveats, and the closing mention of non-existent get_comments/get_transcript parameters spends words on something an agent cannot act on. Reasonable size for the information, but with wasted and misleading content.

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

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

With no output schema, the description carries the return-shape burden and does so by listing post_id, engagement counts, timestamps, and video fields, plus the vanity-URL caveat and the reel-count workaround. The only gap is the dangling reference to optional parameters that the schema does not actually expose.

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

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

Schema description coverage is 100%, so the baseline is 3. The description restates the confirm requirement but adds no format or syntax detail for url, account, or cache_max_age. It also references get_comments and get_transcript parameters that do not exist in the input schema, which weakens rather than strengthens parameter clarity.

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

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

States a specific verb and resource ('Retrieves a single public Facebook post or reel by URL') and enumerates the returned fields, so it is immediately distinguishable from siblings like facebook_profile_posts and facebook_profile_reels. An agent can tell what this tool yields without opening the schema.

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

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

Gives a concrete routing rule: when the public Reel badge count is needed, call facebook_profile_reels and match by post_id. It also notes confirm=true is required for credit-consuming calls. However it does not cover when this tool should be preferred over, e.g., facebook_comments for comment retrieval.

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