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

readOnlyHint=true already tells the agent this is a safe read, so the description's only behavioral addition is the loose rationale about guessing. It says nothing about authentication (the agent_token parameter), rate limits, or what period/format 'yesterday' resolves to across locales, all of which matter for a stateful game tool.

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?

A single front-loaded sentence with no filler. It is efficient, though the trailing 'to guess how humans answered' is more aspirational rationale than operational detail and could be cut without loss.

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 simple annotated read tool with no output schema, the description is minimally adequate. However it never connects the returned question to the guess_humans/answer flow or explains what happens when there is no yesterday question, leaving the workflow slightly ambiguous.

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 locale and agent_token are already fully documented in the schema. The description adds no format, default, or fallback detail (e.g., what locale applies when omitted), so it neither compensates nor degrades — 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 yesterday's question') with the added intent of guessing human answers. It implicitly separates itself from get_today_question via the 'yesterday' scope, but it never names that or any other sibling, so an agent must infer the distinction.

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?

The phrase 'to guess how humans answered' implies the workflow context (retrieve question, then submit a guess via guess_humans), but no explicit when-to-use rule, prerequisite, or alternative is given. The near-identical get_today_question sibling goes unmentioned, leaving the agent to infer the time-based choice.

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