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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false; the description merely repeats this ("Read-only; changes nothing"), earning no credit. The only non-redundant line, "Money is integer minor units (cents)," is irrelevant noise for a tool with zero parameters and no monetary fields. No behavior beyond the annotations is disclosed.

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?

Three very short sentences that are front-loaded, but one of them (money in cents) is entirely irrelevant to a parameterless read-only list tool and fails to earn its place. Brevity is achieved at the cost of substance, not through tight editing of useful 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?

For a zero-param, read-only list tool with annotations covering safety, the description is minimally adequate. However, it omits what the tool actually returns (accounts, post counts, last sync) — that content exists only in the schema description — and contains a distracting, irrelevant sentence, so it is thinner than the low complexity warrants.

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?

The tool takes zero parameters, so the rubric baseline of 4 applies; there is no parameter semantics to add or omit. The stray money-units sentence does not describe any real parameter and neither helps nor misleads here.

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 text is essentially "Instagram accounts," a restatement of the tool name with no verb, scope, or distinguishing detail. The genuinely informative purpose statement (accounts connected to the shop's Instagram feed plugin, with post counts and last-sync times) lives in the schema description, not the tool description. Nothing here separates it from the ~100 sibling tools.

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 gives no when-to-use guidance, no alternatives, and no prerequisites. Usage context (place the feed with section type instagram.feed) is present only in the schema description, so an agent reading the description alone gets no routing signal. It is absent rather than misleading, hence 2 not 1.

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