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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so safety is covered. The description still adds real value: it scopes results to owner-uploaded media only, warns never to remove customer media, and states the prerequisite that a video must be a public HTTPS URL supplied by the owner. It stops short of describing result shape or pagination, so it is strong but not exemplary.

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 is front-loaded in the first sentence, and each following sentence carries a distinct constraint (scope separation, removal safety, add-video routing). Slightly dense but no filler sentences; the add-video sentence is arguably tangential for a read tool yet still earns its place as routing guidance.

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 two-parameter read tool with rich annotations and no output schema, the description covers scope, safety, and the write-path alternative. It only lightly implies the returned shape (resource names for media), so an agent must infer what a media entry looks like, but nothing needed to call it correctly 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% for both site_id and user_goal, so the schema already carries parameter meaning. The description adds nothing about either parameter — it never mentions the site/location selection or the optional user_goal field — 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 — read owner-uploaded photos and videos in the connected listing's media gallery — and explicitly disambiguates from content-calendar posts, which is the most likely confusion given the many content tools. An agent can tell what this returns without opening the 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?

Explains the write-path alternative in detail: to add a listing video, stage video_upload through prepare_google_change using the owner's exact public HTTPS URL. It also implies the removal flow depends on resource names returned here. What is missing is an explicit 'use this when you need to inspect existing listing media' statement and any exclusion relative to other Google read tools such as get_google_profile.

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