add_supported_cryptocurrency

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

The annotations only include idempotentHint: false, so the description carries most of the behavioral disclosure burden. It clarifies that this is a non-idempotent mutating add operation and gives a precondition, but it does not disclose duplicate-handling behavior, success/failure semantics, or side effects if the symbol is already present.

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, no filler. The first sentence states the core action and input; the second gives the decisive usage condition. This is appropriately compact and front-loaded.

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-parameter mutation tool with no output schema, the description covers the action, input format, and when it is needed. The only notable gap is that it does not describe what the API returns or how duplicate submissions are handled, but these are not critical for selecting and invoking the tool correctly.

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 input schema already fully documents coingecko_url with format and example, so schema coverage is 100%. The description adds no significant parameter meaning beyond saying the URL is a CoinGecko coin-page URL, which the schema already conveys.

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 action ('Add'), a specific resource ('supported manual-crypto list'), and the required input mechanism (CoinGecko coin-page URL). It also names get_supported_cryptocurrencies as the related check, distinguishing this write operation from the read-only list operation.

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 explicitly states when this tool is needed: only when get_supported_cryptocurrencies does not already list the symbol. This gives clear when/when-not guidance and points to the sibling tool to consult first.

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