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 structurally. The description adds useful content context — results are verified, Canada-specific, consumer and B2B SaaS, spanning all categories — but omits behavioral facts such as pagination behavior under the limit parameter or whether results are sorted.

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?

A single front-loaded sentence that spends every word on scope: verification status, geography, segment, resource types, and breadth. Nothing is repeated from the title and 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?

For a simple read-only listing tool with one optional parameter and no output schema, the description covers what the tool returns (codes, invite links, bonuses) and the population it covers. Remaining gaps — pagination and result ordering — are minor at this complexity level.

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?

There is a single optional parameter with 100% schema description coverage, so the schema already explains limit and its default of 50. The description adds no additional meaning about paging, truncation, or maximum values, 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?

The description gives a specific verb (List) plus a well-scoped resource: verified Canadian consumer and B2B SaaS referral codes, invite links, and sign-up bonuses. The phrase 'across all categories' signals an unfiltered listing, which partially separates it from siblings like list_business_referral_codes and list_featured_referral_codes, though naming the unfiltered nature explicitly instead of an alternative would sharpen the distinction.

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?

Usage is only implied: 'all ... across all categories' suggests this is the browse-everything call rather than a filtered or targeted search. There is no explicit statement of when to prefer it over search_referral_codes or get_referral_code, and no exclusion guidance.

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