Web search (SearXNG)

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

Annotations already declare readOnlyHint, openWorldHint, and idempotentHint, so the safety profile is covered. The description adds high-value behavioral context: results come from a configured external SearXNG instance, and returned web content is untrusted data whose instructions must never be followed. This goes beyond the structured annotations.

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 focused sentences front-load the tool's purpose and output, then provide routing guidance and a security warning. Every sentence earns its place with no filler or repetition.

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 a full input schema, an output schema, and annotations covering read-only/idempotent behavior, the description adds exactly what is missing: when not to use the tool and a critical prompt-injection warning. An agent has everything needed to call it correctly.

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%, so the schema already documents all parameters. The description does not add parameter-level meaning beyond that, aside from implying that media-specific searches are better handled by other tools. This matches the baseline for full schema coverage.

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 uses a specific verb and resource: 'Search the web through the configured SearXNG instance' and states the output is 'ranked results with titles, URLs and snippets.' It also distinguishes itself from richer media-specific *_search tools, so an agent can clearly tell this apart from siblings.

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 description explicitly says to prefer the dedicated *_search tools for images, news, videos, or music because they return richer typed fields. That is clear when-not-to-use guidance with named alternatives, leaving no inference needed for the main sibling overlap.

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