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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds genuinely useful behavior: results come from LEGI's consolidated in-force base (not historical versions), depth caps the level count, and section_id enables incremental branch expansion across calls.

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 core purpose is front-loaded in the first clause, and the operational hints (depth, section_id chaining) plus the use-case sentence follow efficiently. Minor redundancy with the schema on depth/section_id keeps it from a 5, but nothing is padded.

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 three params, no output schema, and full annotation coverage, the description gives enough to call it correctly: accepted code identifiers are in the schema, depth and drill-down are explained, and the source database is named. Return shape (how headings and article numbers are nested/labeled) is only loosely implied, which is the main remaining gap.

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 mostly restates the schema: 'depth controls how many levels come back' mirrors 'Levels to return below the starting point, 1-8 (default 2)', and the section_id chaining hint repeats the schema's own 'from a previous fr_code_toc answer' note. No additional format or identifier-shape guidance is offered beyond what the schema already documents.

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 resource (table of contents of a French code in force), the heading hierarchy it returns, the article numbers under each heading, and the authoritative source (DILA LEGI consolidated base). It also implicitly separates itself from the article-fetching siblings by framing the tool as structural browsing ('browse the structure ... or list the articles of a chapter').

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?

Gives clear usage context: browse the structure of Code civil / Code du travail / Code de commerce, or list articles of a chapter, and how to drill down via a section_id from a previous answer. It stops short of naming alternatives (fr_code_article, fr_legi_search) or stating when not to use it, so it falls below a 5.

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