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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds nothing beyond that: no mention of result ordering, matching semantics (fuzzy vs exact), catalog scope, or how the second parameter affects behavior, leaving the query behavior opaque.

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?

A single front-loaded sentence with no filler or repetition. It is efficient, though the terseness is a symptom of under-specification rather than disciplined editing.

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, no parameter documentation, and no behavioral detail, the description leaves the agent without enough to call the tool confidently — it does not even clarify what a "capability" is or what a search returns.

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 0% and neither parameter is documented in the schema. The description only weakly implies that "query" is a search string; the "token" parameter is entirely unexplained in both schema and description, which is a real gap for a 2-param tool.

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 resource ("synthetic capability catalog"), which is more than a restatement of the name. However, it gives no indication of how this differs from other discovery-style siblings like extensions_list, knowledge_lens, or platform_describe, so the agent must infer the boundary.

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 contains no when-to-use guidance, no preconditions, and no mention of alternatives. An agent cannot tell from this text whether capabilities_search is the entry point for discovery or a secondary lookup used after extensions_report_gap.

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