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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds useful behavior beyond that: the index is bilingual by default, shared with Agent Surface and WebMCP, has no external provider, and catalog mode uses legacy scoring on title, tags, topics, and description. This gives the agent meaningful execution context without contradicting 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?

The description is two sentences with no filler. The first sentence front-loads the tool's purpose and scope, and the second sentence explains default behavior and the mode distinction. Every clause contributes useful information.

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 search tool with four documented parameters, an output schema, and safety annotations, the description covers the essential context: what is searched, over which content, how the default index behaves, and what catalog mode changes. It is not fully complete only because it does not position the tool against its closest siblings.

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%, so the baseline is 3. The description adds extra meaning by explaining that the default index is the bilingual canonical one and that catalog mode preserves legacy scoring on title, tags, topics, and description. This enriches the mode and language parameters beyond their schema descriptions.

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 verb and resource: full-text local search over l0g.fr content types (analyses, guides, glossary, methodological sheets, primary sources). It clearly separates fulltext and catalog behavior, but it does not explicitly distinguish itself from sibling tools such as search_by_topic or list_recent_analyses, so it falls just short of full differentiation.

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 provides clear context: use it for local full-text search across l0g.fr, with a bilingual canonical index by default and an optional legacy catalog scoring mode. It does not explicitly say when to prefer search_by_topic or another sibling over this tool, so it lacks explicit exclusions and alternatives.

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