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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds non-obvious behavior beyond that: links are returned as ids and never URLs, and a person may appear by invite address or by account id depending on whether they have signed in. It says nothing about permissions required to read, but the added identity/ID semantics are genuinely informative.

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?

Four short sentences, zero filler, with the returned-fields summary front-loaded and the identity caveat placed after it. Slightly dense in clauses, but every sentence carries operational meaning.

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?

Even though an output schema exists, the description usefully previews the shape of the result (visibility, links as ids, grants) plus the identity nuance needed to interpret grants. For a single-parameter read tool with annotations and an output schema, nothing an agent needs is missing.

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?

With a single parameter at 100% schema description coverage, the schema already defines app_id fully, so the baseline is 3. The description implies the app must be one whose sharing is being read but adds no format, acquisition path, or constraint beyond the schema.

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 precise verb+resource ('Reads how an app is shared') and enumerates exactly what is returned: public/private visibility, live share links (ids only), and invited people under grants. This is enough to tell it apart from set_access and revoke-grant, which mutate the same resource.

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?

'For when the person asks who can open an app' gives a clear triggering condition, and 'Giving someone a link means making a new one' steers the agent away from expecting this tool to create links. It does not explicitly name set_access as the mutating counterpart, so it stops short of a full when-not/alternative statement.

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