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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds non-obvious context beyond the annotations: it is an MCP Apps widget (interactive UI) and filtering happens both server-side via query and client-side, which affects how an agent should treat the result. It stops short of describing empty-result or auth behavior, but that is minor given the annotation coverage.

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 tight sentences, front-loaded with the primary purpose, then the exclusion/alternative, then the parameter hint. No sentence is redundant.

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 and a single optional parameter, the description supplies everything needed: what the tool returns (an interactive gallery widget), its scope (ALL verified examples), how filtering works, and when to prefer a sibling. Nothing critical 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 coverage is 100% for the single parameter, so baseline is 3. The description adds meaning beyond the schema's 'Pre-filter examples by keyword': it clarifies that query is a pre-filter and that the widget additionally filters client-side, telling the agent the filter need not be exhaustive.

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 — opening an interactive, filterable gallery of nifra's verified code examples — and names the sibling (nifra_example) it is not. An agent can distinguish it from the other nifra_* tools 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?

Explicitly states the exclusion ('NOT for fetching one snippet as text') and routes to the correct alternative ('use nifra_example for that'). It also frames the intended use case: browsing and discovering what exists.

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