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

Annotations already declare readOnlyHint, openWorldHint and destructiveHint, so the safety profile is covered. The description adds genuinely useful behavioral context the annotations cannot: the legacy/deprecated status and the fact that results come from the federal CanadaBuys source only. It stops short of describing result shape or pagination, keeping it from a 5.

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?

Three short sentences with zero padding; the legacy status and source scope come first, followed by capability and then the preferred alternative. Nothing is repeated from the annotations or the name.

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?

An agent has enough to decide between this tool and search_opportunities, and the read-only annotations plus fully documented schema cover the remaining risk. Only the return format (e.g., contract summaries vs. full records) is left unspecified, which is minor for a no-output-schema list tool.

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%, with all three parameters (limit, keywords, province) documented in-schema with examples. The description mentions keyword and province filtering but adds no semantic detail beyond the schema, so the baseline 3 applies.

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 the specific resource and its source scope ('Legacy: federal CanadaBuys only') and names the filtering capability, so an agent can tell exactly what corpus it searches. It explicitly contrasts with the sibling search_opportunities, which is the closest alternative.

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 an explicit routing rule: 'Prefer search_opportunities for combined CanadaBuys and Alberta APC results,' naming both the alternative and the condition that selects it. 'Legacy' also signals this should be a fallback rather than the default choice.

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