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

Annotations already declare readOnlyHint and openWorldHint, but the description adds substantial behavioral context: eligibility rules for each surface, that shipping-in-silence and accelerating take no other argument and return at most 100 rows, that builder-radar accepts query/radar/limit/offset, and that results are not ordered by price. These details go well beyond what the annotations provide.

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 description is one long, dense paragraph that packs all surface definitions and rules together. While the purpose is front-loaded, the remaining information is hard to scan and would benefit from bullet points or clearer segmentation. Given the tool's complexity, the length is somewhat justified, but the structure is poor.

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 tool with 12 surfaces and 18 parameters, the description covers the surface semantics thoroughly and notes key constraints like max rows for certain surfaces. It does not explain return format or pagination beyond offset, but the absence of an output schema means that is less critical. Annotations already cover read-only and open-world behavior, so overall the description is nearly complete.

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 already 83%, so the baseline is 3. The description goes further by defining each surface enum value in detail and clarifying which parameters apply to which surfaces (e.g., builder-radar takes query, radar, limit, offset; shipping-in-silence and accelerating take no other argument). This adds meaningful semantics beyond the schema.

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 and resource: 'Find Robinhood Chain projects by name, ticker or contract, or browse one of HEY's surfaces.' It also distinguishes itself from lookup_token by explaining that a full 0x address is answered as lookup_token would. An agent can tell this is a project search/browse tool, not a token lookup or market 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?

The description implies when to use it by listing surfaces to browse, and it notes that a full 0x address is handled like lookup_token. However, it never explicitly says when to choose this tool over siblings like ask_hey, compare_projects, or lookup_token. The guidance is implicit rather than explicit.

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