search_instance_icons

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

With no annotations, the description carries the full burden and mostly does: it discloses the auth/configuration requirement (NEXT_UI_INSTANCE_URL and credentials) and that results are drawn from the instance's real now-icon package. Read-only semantics and any rate/limit behavior are left implicit.

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 core purpose, then usage guidance and result-format details. The sentence about reading from the now-icon package is somewhat redundant with the opening claim but still reinforces authenticity; otherwise every sentence earns its place.

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?

There is no output schema, so the description must explain return shape, and it does: base names in dash-case with suffix conventions. Combined with disclosed auth prerequisites and validation behavior, an agent has enough to call it correctly, though no pagination/limit guidance is offered beyond 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 baseline is 3, but the description goes further by explaining what `query` values match and how the returned base names map back to an `icon` property via -outline/-fill suffixes. It adds retrieval semantics rather than merely restating parameter types.

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 (searches) and resource (the icon library on the configured ServiceNow instance), and scopes it to the `icon` property of named HDS components. An agent can distinguish it from search_instance_components, which deals with components rather than icons.

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?

"Use this BEFORE picking an icon name instead of guessing" gives explicit timing guidance, and the note that passing a full name also validates the base icon adds a clear secondary use case. No when-not condition or named alternative sibling is offered, 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.