x_search

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

Annotations already cover safety (readOnly, non-destructive, openWorld). The description adds genuinely useful context beyond them: the return shape (summary, structured posts, source URLs, execution counts), the OAuth auth path, and the important caveat that results are sampled rather than a complete archive.

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?

Four short sentences, front-loaded with the core purpose followed by return behavior and the sampling caveat. No filler, though the auth-mechanism detail is slightly more than an agent needs to select the tool.

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?

No output schema exists, so the description appropriately covers return contents and the sampling limitation, and it notes caching behavior. The main residual gap is parameter-level detail for query and max_results, but overall it is sufficient to call the tool 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?

With 67% schema description coverage, the schema documents dates, cache_mode and allowed_x_handles. The description only calls out cache_mode=refresh, adding marginal meaning without explaining query construction or max_results behavior, so the baseline 3 fits.

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 (Search) and precise resources (public X/Twitter profiles, posts and threads), plus the underlying mechanism (native xAI X search via local magpie OAuth). No sibling tools exist, so no differentiation is needed, but the purpose is unambiguous and concrete.

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?

Offers one actionable usage hint ('Use cache_mode=refresh for a fresh lookup') and manages expectations ('Results are retrieved samples, not a complete archive'). However, there is no explicit when-to-use versus when-not-to-use guidance and no guidance on choosing between the other cache modes.

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