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

With no annotations, the description carries the burden, and it does add real value by disclosing that the returned content is user-generated and should be treated as untrusted input (a security/prompt-injection warning absent from structured fields). However it omits auth requirements, pagination/return shape, and does not explicitly confirm the read-only, side-effect-free nature of the lookup.

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?

Two short sentences, front-loaded with the core purpose, followed by the disambiguation and trust caveat. No wasted text.

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?

There is no output schema, so some return-value explanation would normally be needed, but the description does characterize the returned payload as user-generated TikTok content. Combined with the clear routing note, it is nearly complete for a single-parameter lookup, with only return fields unaddressed.

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% with a single parameter whose description ("TikTok video ID (pk)") matches the description's "by pk" phrasing. The description adds no syntax or format detail beyond what the schema already provides, so the 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?

States a specific verb and resource ("Get a TikTok video by pk") and explicitly distinguishes itself from the sibling get_media_by_code, explaining why it exists separately (TT has no shortcode field). An agent can identify and route to it without opening another 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?

Names the IG alternative it replaces and gives the reason for divergence, which effectively tells an agent when to pick this over get_media_by_code. It does not, however, state exclusions or when NOT to use it (e.g. vs search_tt_media_captions or get_tt_user_medias).

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