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

Beyond the annotations (readOnlyHint, idempotentHint, destructiveHint=false), the description discloses that the preview URL works anonymously, expires after previewExpiresInSeconds, and is renewed by calling the tool again, plus that the tool changes nothing about the Riddle. It also explains the draft/live split via isPublished and viewUrl.

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 the core purpose in the first clause and every sentence carries actionable content. It is dense with parenthetical detail, but nothing is clearly wasteful.

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?

An output schema exists, so return values need not be explained, yet the description still covers the non-obvious parts: client-dependent rendering, URL expiry/anonymous access, and the isPublished/viewUrl state. Nothing an agent needs to invoke it correctly 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?

Only one parameter (UUID) and schema description coverage is 100%, so the schema already carries the semantics. The description adds no syntax or format detail beyond what the schema provides, making the baseline 3 appropriate.

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 ('Shows the user the current DRAFT of a Riddle as a playable preview') and immediately scopes it as the draft, not the live version. This clearly separates it from siblings like riddle_get and riddle_publish.

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 when to call it (after riddle_builder_create or riddle_builder_update, when the user wants to see the result) and when not to ('do not call it on every edit of a multi-step build, once at the end is enough'). It also handles the riddle_publish edge case by noting draft and live are identical right after publishing.

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