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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing the substance of the answer (trade agreements, foreign-bidder rules, registrations needed), which tells the agent what the result will contain. It does not mention latency, caching, or coverage caveats.

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 sentences, both front-loaded: the first defines the answer, the second defines the invocation condition and inputs. No filler or redundant restatement of the title.

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 has to convey what comes back; it does so by listing the factors the answer weighs (trade agreements, foreign-bidder rules, registrations). Combined with full schema coverage and read-only annotations, an agent has enough to call it correctly, though the response shape (boolean vs. explained verdict) is not stated.

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 schema already documents all three parameters, including the 'not needed if tender_id is given' relationship. The description's 'Give a tender_id or the tender's country' merely restates that either/or semantics without adding format or precedence detail. Baseline 3 is appropriate.

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 precise question the tool answers ('Whether a company based in one country may bid for public tenders in another country') and enumerates the considerations involved (trade agreements, foreign-bidder rules, registrations needed). The cross-border framing clearly separates it from the sibling check_my_eligibility, which concerns the user's own eligibility.

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?

It gives an explicit trigger: 'Use when the user asks whether a company from one country can bid on, or take part in, public tenders in another country.' It also tells the caller what input to supply ('Give a tender_id or the tender's country'). It stops short of naming alternatives or stating when not to use it versus check_my_eligibility or get_requirements.

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