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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, and the description adds real context: the level taxonomy, the exact facts returned, what is missing for the next level, and the side behavior that credential=true also mints a signed credential and a one-hour kya+jwt token. The only shortfall is that it doesn't note any auth or rate requirements for obtaining a signed credential.

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?

Front-loaded with the primary outcome (the RS-KYA level) followed by the return detail, the optional credential behavior, and a call example. All content earns its place, though the opening sentence is dense enough that it would benefit from being split.

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?

An output schema exists, so return values need not be spelled out, yet the description still summarizes them usefully, and annotations carry the safety profile. The one substantive gap is that it never positions itself against the sibling kya_check/kya_verify tools, which is the most likely source of mis-selection.

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 50%: 'agent' is documented in the schema but 'credential' has no schema description at all. The description compensates directly by explaining what credential=true returns, and the embedded call example clarifies the required agent format beyond the schema's type/title. This is meaningfully more than the schema provides.

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 clear verb (look up) and resource (an agent's RS-KYA level) and even enumerates the returned facts and the L0/L1/L2 level taxonomy. It does not, however, distinguish this from the sibling tools kya_check and kya_verify, so an agent cannot tell from the text alone why it would pick kya_lookup over those.

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?

There is no when-to-use guidance and no mention of the closely related siblings kya_check and kya_verify, which is exactly where routing guidance is needed. The only contextual hint is that the token from credential=true is 'to present to other services', which implies a use case but not a selection rule between tools.

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