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

Annotations already establish readOnly, idempotent, non-destructive, closed-world, so safety is covered. The description adds genuinely new behavior: newest-first ordering, the tracking start date (Sep 27 2026), and plan-based result truncation, which is effectively a limit/quota disclosure the agent needs to interpret partial results.

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?

Dense but single-purpose: scope and ordering come first, the returned fields follow, and the tier constraint closes it out. The one-sentence run-on listing of fields is slightly hard to parse but every clause carries information, and no sentence is wasted.

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 the description carries the return-value burden and does so well, enumerating when, title, version count, post-update player comparison versus the prior week, the change, and the typical change. It also discloses plan-based truncation. Only error behavior and the exact meaning of the comparison window are left implicit.

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%, so both parameters are documented in the schema, which sets the baseline at 3. The description's only additions are reinforcing the tier-dependent limit ('Free and Plus see the last 10') and describing the game argument's accepted forms, both of which the schema already states.

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?

The description gives a specific resource and scope: 'Every update of one Roblox game since tracking began (Sep 27 2026), newest first'. That is far more than a restatement of the name, and an agent can tell this apart from list-style siblings like charts or trends. It stops short of naming a sibling it must not be confused with, so a 4 rather than a 5.

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?

Usage is implied rather than stated: the tool is for one game's update history, and the tier note ('Free and Plus see the last 10; Pro and Studio see every one') tells the agent the result window varies by plan. There is no explicit when-to-use / when-not, no mention of alternatives such as trends or days, and no prerequisites for the required game parameter.

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