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

Annotations already cover read-only, open-world and non-destructive behavior, but the description adds genuinely new traits: results are sorted by performance, and the call costs no credits. What's missing is any note on recency window ('lately' is undefined) or result volume behavior beyond the limit parameter.

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 sentences, front-loaded with the return shape and immediately followed by the differentiator. The final sentence packs return field details and three downstream tool hints together, which is dense but each fragment carries actionable information.

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 does the work of describing the return ('posts[] with post_id', plus hook, topic, pillar, funnel stage and numbers), which is adequate for a two-optional-parameter read tool. The underspecified recency window ('lately') is the only notable gap.

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 both limit (default 8, max 50) and platform (enum of instagram/tiktok/youtube) are already fully documented. The description adds no additional meaning about these parameters, so the baseline of 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?

States a specific verb and resource ('Returns what every tracked creator posted lately'), the ordering ('highest performing first'), and the fields carried per post. It explicitly contrasts with the sibling get_creator_report (one creator in depth, full script), so the agent can tell the two apart without opening 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?

Gives an explicit when-to-use ('plan from what works across all tracked creators') and names the alternative with its distinguishing condition ('get_creator_report covers one creator in depth and returns a post's full script'). It also routes downstream: post_id feeds save_inspiration, generate_content remix, and show_posts.

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