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

With no annotations, the description carries the burden well: it declares read-only ('nothing changes'), explains that human and service-account principals share the same email-keyed row, and describes the return shape (account-level plus per-app values). It omits auth/permission requirements and error behavior, keeping it short of a 5.

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-loads purpose and read-only guarantee, then the grant_app_permission dependency. Slightly dense in the final clause, but every sentence contributes and nothing is redundant.

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?

No output schema exists, yet the description explains what is returned (account-level permissions and per-app values), which is the key gap it must fill. It lacks detail on failure cases or what happens if the email is unknown, so not quite complete for a 4-param tool.

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 coverage is 100%, so baseline is 3; the description earns more by clarifying that both human and service-account emails resolve to the same user row keyed by email, which adds meaning to target_user_email beyond the schema text. It says nothing extra about notification_message, but the schema already documents it.

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 one principal's current Play Console permissions by email') and distinguishes itself from the sibling mutation grant_app_permission. The agent can tell exactly what is returned and what is not (no writes).

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?

Explicitly names the prerequisite relationship: 'This is the prerequisite before grant_app_permission' and instructs reading current grants first and confirming with the user. Alternatives and sequencing are spelled out, not inferred.

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