x_search

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

Annotations only declare readOnlyHint=true; the description adds meaningful behavioral context beyond that: complementary queries may run in parallel, stopping/termination behavior, conditions for deepening, and the return format ('raw xAI Responses API body'). No contradiction with the read-only annotation.

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?

Five functional sentences with the primary purpose front-loaded and every sentence earning its place — scope, routing, stopping, deepening, and fetch delegation. Slightly dense but appropriate given the multiple behavioral rules it must convey.

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?

Comprehensive for a search tool covering multiple content types with parallelism, termination, and delegation rules. With no output schema present, the description still discloses the raw response body. Nothing an agent needs to invoke this correctly 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% since the query parameter is fully documented ('The question or search query to investigate'). The description adds little parameter-specific detail beyond the schema, so the baseline of 3 applies. Parallel-execution hints imply query handling but don't add syntax or format value.

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 specific resource (X posts, accounts, threads, replies, trends) with a clear search intent, and explicitly routes around siblings by saying 'Prefer it over web_search for X content.' An agent can distinguish x_search from web_search and web_fetch without opening schemas.

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?

Provides explicit when-to-use scope (X content), preference over web_search, a stopping condition ('Stop when the requested official post or account result is found'), a deepen-only-on-conflict rule, parallel-execution guidance, and explicit delegation to web_fetch for external pages. This is model guidance with clear exclusions.

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