resolve_vanity_url

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

Annotations already cover readOnly/idempotent/destructive hintsщие, so the description's bar is lower. It adds the API key requirement and the return format ('all common formats, or not-found'), which are useful beyond annotations. No contradiction.

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 short sentences plus one use-case sentence. Front-loaded purpose in line 1, immediate usage context, and expected return behavior. No wasted words.

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?

The output schema (not shown in full but flagged as present) would document return details, and the description already states the ID formats and not-found case. API key requirement is noted. Rate limits or failure modes are missing, but for a simple idempotent one‑parameter lookup this is sufficient.

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 already describes the vanity parameter with a description and examples; description adds an extra example (gabelogannewell) and clarifies the input format by referencing the URL pattern. With 100% schema coverage, this baseline is adequate but not extensive.

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+resource: resolve a Steam custom URL name to SteamID64. It clearly distinguishes from sibling tools that operate on already-resolved SteamIDs (e.g., get_player_summary, get_owned_games), so an agent knows when to choose this tool.

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 states the trigger condition ('when you only have a person's custom URL name and need the numeric id that other tools consume') and notes the API key requirement. No explicit exclusions or alternative tool names, but the purpose statement already implies when not to use it (when you have the numeric ID).

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