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 burden is off the description. The description still adds real behavioral context: counts follow the same rules as list_tenders and open counts exclude expired deadlines, which materially affects how an agent interprets the numbers returned.

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 in the first clause, followed by usage scope, counting rule, and examples in a sensible order. The sentence 'One optional parameter (include_dead)' is redundant with a 100%-covered schema and is the one line that does not earn its place.

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 only one optional parameter and no output schema, the description carries the return-shape burden and does so (per-portal counts and status). The counting-rule caveat prevents misinterpretation of the numbers; only the absence of any routing to list_tenders/get_tender_counts leaves a small 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 description coverage is 100%, so the single parameter's meaning ('include notices with dead portal URLs in the counts') is already fully documented. The description only restates its existence ('One optional parameter (include_dead)') and adds the related counting rule, which is a marginal increment over the schema.

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 ('Lists the tender portals the notices come from') and immediately defines the payload: number of notices per portal plus status. It also names concrete portal examples (EU TED, federal portal), which makes it unmistakable that this is an aggregation-over-portals tool, not a notice search.

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?

Explicitly scopes usage to 'requests where the user asks which portals are covered or how many notices come from a given portal' and backs it with three concrete example user questions. It does not state exclusions or name the sibling to use instead (e.g. list_tenders / get_tender_counts for notice-level or total counts), so it stops short of full routing guidance.

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