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

Annotations only declare readOnlyHint=true and openWorldHint=false. The description adds real behavior beyond that: the 7-day recency window, returning shops ranked first, and the fact that each row carries the last-engaged timestamp. It omits result-count/pagination behavior, though limit is capped at 100 in the schema.

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?

Purpose and selection rule are front-loaded, then filters, then the next-step chain — a clean ordering. The only slightly expendable clause is the parenthetical justification for returning-first ordering.

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 reasonably (ordering, last-engagement field). It stops short of describing result volume or how to page through a large city list.

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 coverage is 75% and both enums (mode, type) are already documented there, including mode's 'all' default. The description names the same three filters but adds no syntax or format detail beyond the schema, and never mentions the limit parameter. Baseline 3 applies.

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?

Names a precise resource (directory businesses with matched Instagram handles) and a precise selection rule (DUE — never engaged, or not engaged within 7 days either side of today). An agent can distinguish this targeting tool from ig_comment_queue or my_instagram_posts without opening any 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?

Clearly frames the use case and chains the follow-up workflow: fetch posts, pick a recent post, then queue_ig_comment. It does not, however, state when NOT to use it or how it relates to ig_comment_queue/my_prospects as alternatives.

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