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

Annotations are empty, so the description carries the behavioral burden. It adds one useful constraint: only accounts the authenticated user is allowed to view are returned. It does not mention that the operation is read-only, what happens on unauthorized access, or return/error behavior, but for a simple fetch-by-ID this is moderate disclosure.

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?

The description is a single sentence with no wasted words. The core action, scope, and platform coverage are all front-loaded efficiently.

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?

For a one-parameter fetch tool with no output schema and no annotations, the description covers what is fetched, who may view it, and which platforms are supported. It does not describe the returned account shape or failure modes, but the low complexity and complete parameter schema mean little is missing for a correct call.

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 schema already documents account_id. The description repeats the 'on any platform' nuance from the schema but adds no meaningful parameter-level semantics beyond that, so the baseline score of 3 is appropriate.

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?

The description states a specific verb ('Fetch'), a clear resource ('a single posting account'), and the access scope ('the authenticated user is allowed to view'). It also names the supported platforms (TikTok, Instagram, YouTube), which distinguishes it from sibling create/update/delete/list account tools without needing to inspect their schemas.

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?

The description clearly indicates this is for fetching one account by ID, and the word 'single' implicitly differentiates it from list-accounts-tool. However, it does not explicitly state when to prefer an alternative or provide exclusion conditions, so it stops short of a 5.

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