Resolve an Untappd URL

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, and the description adds meaningful behavioral context: 'Pure local parsing — no network' and the fact that it returns a routing decision. There is no contradiction between the description and the annotations.

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 with no filler. The action, input scope, output, and key behavioral property (no network) are all front-loaded. Every sentence earns its place.

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 one-parameter resolver with no output schema, the description conveys the essential return semantics: entity type, entity id, and the next tool to call. It does not cover invalid/unsupported URL behavior, but that is a minor gap given the tool's simplicity.

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?

The schema already documents the 'url' parameter with 100% coverage, and the description adds value by explaining which URL forms are valid and what the resolver extracts from them. This goes beyond the schema's generic 'An untappd.com URL to resolve'.

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 states a specific verb ('Parse'), a specific resource ('untappd.com URL'), and a concrete output ('entity type and id, and name the tool to call next'). The enumerated URL path forms (/b/, /w/, /v/, /user/, check-in) make its scope clear and distinguish it from sibling tools that fetch or search data.

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 description gives clear context for when to use this tool: when you have a raw Untappd URL and need to determine the entity type and route to the next appropriate tool. It also clarifies the local, no-network nature. However, it does not explicitly say when not to use it or compare it with the similar-looking sibling untappd_open_url.

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