hero_schema

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely useful behavioral detail beyond them: no-argument calls list all queries and mutations with their arguments, while a type argument lists that type's fields. It does not mention rate limits or return size, but for a read-only introspection tool this is substantial added context.

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?

Three short sentences, each earning its place: purpose, default behavior, parameterized behavior, and routing guidance. Front-loaded with the core action and free of filler.

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-optional-parameter, read-only introspection tool with no output schema, the description covers both invocation modes and what each returns, plus when to prefer it over its sibling. Nothing an agent needs in order to call it correctly is missing.

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 100% and the schema already documents the 'type' parameter with an example ('Contact'). The description adds only a use-case hint (inspect the return type of calendar_events) and notes the parameter is optional, so baseline 3 is appropriate.

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?

States a specific verb and resource ('Explore the HERO GraphQL schema') and immediately explains the two distinct operating modes, so an agent knows exactly what the tool produces. It explicitly positions itself against the sibling hero_graphql, making it distinguishable without opening any schema.

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?

Gives a concrete routing rule: 'Use this before hero_graphql or when you need filter arguments.' That names both the alternative tool and the trigger condition for choosing this one, leaving little to inference.

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