ls_list_license_key_instances

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

The description adds significant behavioral context beyond the readOnlyHint/true and destructiveHint/false annotations. It discloses pagination behavior ('check meta.page...'), and importantly reveals an environment-dependent requirement (LEMONSQUEEZY_ALLOWED_STORE_IDS) and the true security boundary ('the API key's visibility is the true boundary'). This goes well beyond the annotations.

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?

The description is relatively concise and front-loaded with the main purpose. However, the cross-store note becomes run-on and grammatically awkward ('Even with that set, Pair with a scoped LemonSqueezy API key'), which slightly undermines structure. It still earns a 4 for packing useful info without excessive length.

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?

The description covers the core aspects of a list tool: resource, optional filters, pagination response, and a special environment condition. It lacks an explicit explanation of the 'instance' concept beyond 'activations' and doesn't describe the response shape (but no output schema exists, so the meta.page mention helps). For a list operation with schema-provided params, this is reasonably complete.

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%, so baseline is 3. The description adds extra meaning to licenseKeyId by noting it becomes required under a specific configuration, which is not evident from the schema alone. It also implies that include/pageSize/pageNumber relate to list behavior, but doesn't detail them beyond schema descriptions. Overall, it adds non-schema context, justifying a 4.

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 opens with a specific verb+resource: 'List all license key instances (activations), optionally filtered by license key.' This clearly distinguishes it from sibling tools like ls_list_license_keys (different resource) and ls_get_license_key_instance (single-instance fetch). The parenthetical 'activations' further disambiguates the domain concept.

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?

The description provides clear context: it's for listing instances with optional filtering and pagination. It includes a cross-store note explaining when licenseKeyId becomes required (when LEMONSQUEEZY_ALLOWED_STORE_IDS is set), which is useful usage guidance. However, it does not explicitly state when to prefer an alternative tool, though 'list' vs 'get' distinction is implicit.

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