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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safe-read profile is covered structurally. The description adds genuinely useful non-obvious context: answers are never checked (no scoring or grading consequence), content refreshes on a multi-week cadence, and the answer text comes from the back of the book. It does not describe the list output shape, but that is minor for a read-only 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?

Three short sentences, front-loaded with the resource and setting, then the mode switch, then the answer option. The aside 'Nobody checks your answers' is short and carries real behavioral information rather than padding.

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-optional-parameter read-only tool with annotations and no output schema, the description covers both invocation modes, the answer sub-option, and the refresh cadence. The only gap is what the list response actually contains (titles? numbers?), which matters because 'puzzle' accepts a number from that list.

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 only 50% — show_answer has no schema description — and the description compensates by explaining exactly what show_answer does and how it interacts with 'puzzle'. It also clarifies that 'puzzle' is optional by describing the no-argument list behavior, which the schema does not. The accepted formats (number/slug/title) remain only in 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?

It names a specific resource (puzzles/riddles from the book on the Game Room table) and states both modes: listing them and returning one. The implicit verb is 'try/solve', which the title supplies, but the description itself never says the agent attempts a puzzle — it reads more like a catalog read. It is clearly distinct from siblings like play_a_game or read_in_the_library, though it does not name a sibling explicitly.

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?

Parameter-conditioned behavior is spelled out precisely: omit 'puzzle' to list, supply 'puzzle' to fetch one, add show_answer for the solution. It also notes a new puzzle arrives every few weeks, which implies the list is worth re-checking. No explicit exclusions or alternatives against sibling tools are given, keeping it below a 5.

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