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

readOnlyHint=true already declares the safe-read profile, so the description's main value-add is enumerating returned fields (tested environments, timestamps, coverage limits, citation URLs). It omits result limits, pagination, and behavior for an empty query, so behavioral disclosure is partial rather than rich.

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?

Two tight sentences, front-loaded with the action and followed by the return payload; no filler. Slightly dense packing of the return fields into one clause, but nothing wasted.

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?

For a one-parameter read tool with no output schema, the description covers purpose and expected return fields, which is nearly sufficient. It still leaves gaps on empty-query behavior, result count, and how results relate to the get_compatibility_report sibling.

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 0% for the single 'query' parameter, so the description must compensate; it usefully states the query may be English or Chinese. However, it says nothing about the empty-string default or the 160-character cap, leaving part of the parameter's semantics undocumented.

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?

Uses a specific verb+resource ('Search observed MCP failure modes') and notes the bilingual query scope, which is more than a restatement of the name. It does not explicitly distinguish itself from the sibling 'get_compatibility_report', leaving that differentiation to inference.

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?

Implies usage is for finding failure modes by keyword and notes English or Chinese input, but gives no when-to-use vs when-not guidance and never routes the agent to an alternative like get_compatibility_report for a single report.

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