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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds a genuinely useful cost signal ('[호출당 10포인트]' – 10 points per call), but says nothing about failure modes for private/deleted posts or any rate limits.

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?

Front-loaded with the resource and the returned fields, then the cost note last, which is the right order. The English and Korean sentences are verbatim translations of each other, so roughly half the text is duplicated for the bilingual audience.

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 correctly enumerates the return fields (text, time, likes, reposts, replies, views, hashtags, media URLs) and discloses the per-call cost. For a one-parameter read tool this is nearly complete; only error/edge-case behavior is absent.

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% and the single parameter carries its own example URL, so the schema does the heavy lifting. The description only restates 'by URL' and adds no format or validation nuance beyond what is already structured.

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 ('X (Twitter) post by URL') plus the exact fields returned, so the agent knows it retrieves a single post's content and metrics. It does not distinguish itself from the sibling x_profile (profile-level vs post-level), leaving minor ambiguity in a crowded social-media toolset.

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?

There is no statement of when to use this tool versus alternatives such as x_profile, instagram_post, or tiktok_profile, and no prerequisites or exclusions. The URL requirement is implied only by the schema, not framed as guidance.

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