SpinTheWheel Hub

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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds genuinely new context beyond the annotations: no account is required, and the returned link is "ready-to-spin" but no spin is executed. It does not say whether links expire or persist, which is the main remaining behavioral unknown.

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?

Two sentences, both earning their place: the first defines the output and the key constraint, the second lists usage contexts. Nothing is repeated from the title or restated from the schema.

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?

With an output schema present and 100% parameter coverage, the description only needs to frame purpose, usage, and side effects, and it does. The missing piece is link lifetime/persistence, which matters for a share-oriented artifact but is not addressed.

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%, including the weights odds scale and the duplicate-removal rule, so the schema carries parameter meaning. The description only echoes the entries prefill and says nothing about title or weights, which is acceptable only because the schema is already thorough.

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 ("Create a ... SpinTheWheel Hub link") plus a distinguishing constraint ("prefilled with the given entries, without spinning"). That last clause separates it cleanly from spin_wheel without the agent having to open either schema.

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?

Enumerates concrete scenarios for use: the user spins it themselves, shares with a group, projects it, or uses it in class or on stream. The "without spinning" framing contrasts implicitly with spin_wheel, but neither sibling (spin_wheel, list_wheel_templates) is named explicitly as an alternative, so it stops short of full routing guidance.

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

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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, so the safety profile is covered. The description adds that entries are returned alongside each template, but says nothing about ordering, size, or how entries are formatted (and no output schema exists to compensate).

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?

The purpose and the when-to-use instruction are both front-loaded, and nothing is redundant. The long parenthetical enumerating every template family is a little heavy but does real work by telling the agent which wheels exist.

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 single optional-parameter read tool with full annotation coverage and no output schema, the description says what it returns at the level of content and when to reach for it. Only the shape/ordering of the returned entries is left unspecified.

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% and the category parameter's own description supplies example values. The description never mentions the filter, though the listed families loosely hint at valid categories; baseline 3 applies when the schema carries the load.

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?

Uses a specific verb (List) plus resource (ready-made wheel templates) and enumerates the template families, so an agent knows exactly what comes back. It is clearly distinct from spin_wheel (which spins) and create_wheel_link (which shares).

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?

States the triggering condition explicitly: call it before spin_wheel when the user names a common wheel but supplies no options. It also names the follow-up tool, so the sequence is unambiguous.

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

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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds real substance beyond them: the winner is drawn server-side with a cryptographically secure RNG, weights are honored, duplicates are removed, and an animated wheel is rendered in chat. It also instructs the agent to report the winner from the result text rather than inventing one, which is valuable behavioral guidance. Minor gap: no mention of latency, rate limits, or what happens on malformed input.

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 purposeful sentences with the core action front-loaded and the exclusion last, which is the right ordering. The long tracking URL with UTM parameters is the only mildly wasteful element, though it is functional rather than filler.

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 read-only, non-idempotent randomness tool, the description covers inputs, the drawing mechanism, weighting, rendering, and how to consume the result. Since an output schema exists, it does not need to enumerate return fields, so nothing an agent needs in order to call 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?

Schema description coverage is 100%, so the schema already explains title, entries, and the 1–10 weight scale and ordering. The description only restates that weights are optional and respected, adding no syntax or edge-case detail beyond the schema. Baseline 3 is appropriate when the schema does the heavy lifting.

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?

Opens with a concrete verb+resource ("Spin a random picker wheel") and enumerates the decision categories it covers (names, places to eat, teams, giveaway winners, yes/no). It is unmistakably distinct from the siblings create_wheel_link and list_wheel_templates, which build or list wheels rather than draw a winner.

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?

Gives an explicit trigger list ("pick, draw, choose randomly, decide for them, or spin a wheel") and an explicit exclusion with a redirect: Secret Santa draws should go to the external URL instead. Both the when and the when-not are stated rather than left to inference.

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