list_chains

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

With no annotations, the description carries the burden. It discloses that the tool is 'Free' (a cost trait) and implies a read-only list operation. However, it doesn't detail potential side effects, rate limits, or response structure. Given the simplicity of a parameterless listing tool, this is adequate, but not exhaustive.

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 entire description is a single sentence that front-loads the main purpose ('Supported chains, their indexed tokens and venues') and then provides usage guidance. There is no redundancy or filler, making it highly efficient.

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 parameterless tool with no output schema, the description tells the agent what the tool returns (chains, tokens, venues) and when to use it. This is sufficient for the agent to decide to call it without additional details.

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 tool has 0 parameters, so schema coverage is trivially 100%. The description doesn't need to explain parameters; instead it describes the resource output, which is the relevant information for the agent. This meets the baseline for a zero-parameter tool.

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 clearly states the tool lists supported chains, their indexed tokens, and venues. It uses a specific verb ('list') and resource ('supported chains, indexed tokens, venues'), and distinguishes itself from siblings by positioning as the first call for disambiguation.

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 to use it: 'the right first call if you are unsure which chain or ticker to use.' This provides clear usage context and differentiates it from sibling tools that answer specific queries.

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