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

Annotations only say the call is read-only and closed-world; the description adds real behavioral detail: data.sommaire may be null with a reason in data.note, pre-2002 summaries come from scanned issues (source, titles_held_back, complete), Morocco returns supplements with no summary, Tunisia gives no PDF link, and older Algerian years return key_required without a key. That is exactly the non-obvious failure and payload context an caller needs.

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?

Purpose is front-loaded and every block is informative, but the passage is long for a 4-parameter tool and repeats content already in the schema (the continuous Morocco series example 7522, the within-year Tunisia example 97, and the free-tier restriction on year). The country paragraphs also repeat 'data.sommaire is always null' twice, which could collapse into one clause.

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?

There is no output schema, so the description carries the full return-shape burden, and it does: links, sommaire structure, note, source, titles_held_back, complete, supplements, and null-summary cases per country. Combined with existing annotations, an agent has everything needed to call it and interpret the response.

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% and the enum count is 1, so the schema already explains lang, year, number and country, including the same Morocco/Tunisia number conventions. The description largely restates those conventions rather than adding new semantics, so the baseline of 3 applies despite the added examples.

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 and resource ('Get one issue of the Algerian Journal Officiel by year and number') and immediately enumerates what it returns: edition links plus the summary of published texts. It is clearly separable from list_jo_issues (which finds numbers) and get_jo_act/search_jo_text (which look at texts).

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?

'Use it to find which texts an issue published' gives the operative context, and the description points at list_jo_years and list_jo_issues for the parameters, plus the free-tier rule (only Algeria, current year and two before). It stops short of an explicit 'use search_jo_text instead when you only know a keyword' exclusion, so not a 5.

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