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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, covering the safety profile. The description adds a return cap ('up to 50 posts at a time'), which is useful pagination context, but it largely repeats the schema's maximum limit of 50 and adds no auth, rate-limit, or further behavioral detail.

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 short, front-loaded sentences with no wasted words. The purpose comes first, followed by filtering support and then return volume. The last sentence is somewhat redundant with the schema's limit maximum, but it still helps set expectations.

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 simple list tool with four fully described parameters, rich annotations, and no output schema, the description covers purpose, filters, and return cap. It omits explicit offset/pagination mechanics, but the schema documents offset and defaults, so the definition remains adequate.

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 all four parameters are fully documented in the schema. The description mentions filtering by status and platform, which maps to two of the four parameters, but adds no syntax or defaults beyond the schema. Baseline 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?

States a specific verb+resource+scope: 'List the user's social media posts.' An agent can distinguish it from mutation tools like publish_post or schedule_post by the 'List' verb. However, it does not differentiate from related read siblings such as get_post or get_top_posts, so it falls short of a 5.

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 implies usage ('List the user's social media posts') and notes filtering capabilities, but gives no explicit when-to-use guidance relative to alternatives. It does not say when to use this instead of get_post, get_top_posts, or list_comments.

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