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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so safety is covered. The description adds genuinely non-structured information: the $0.25 USDC x402 cost, which an agent needs before calling. It doesn't cover not-found behavior, but the core behavioral gaps are filled.

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 purpose and field coverage are front-loaded in one dense sentence, followed by use context and cost. The field enumeration is long but each item is informative rather than filler; there is no redundant restatement of the title.

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?

With no output schema, the description compensates by listing the returned data categories (ratings, debt, pension/OPEB, revenue sources, EMMA/MSRB links), which tells the agent what it will get. Cost and the optional language parameter are also addressed via the schema.

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 coverage is 100%, so both parameters are fully documented in structured fields. The description's issuer-type enumeration loosely reinforces the 'lookup' parameter semantics but adds no syntax or format detail beyond the schema, so baseline 3 applies.

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+resource ('Municipal bond issuer research for any US issuer') and enumerates the issuer types covered, which lets an agent separate it from siblings like interzoid_university_info, interzoid_city_standard, or interzoid_gov_contracts 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?

The 'For muni bond research, credit analysis, and public finance' clause gives a clear use context, which most siblings lack. It does not name an alternative tool or state when-not to use it, so it stops short of a 5.

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