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

Although annotations already declare readOnly, idempotent, and non-destructive behavior, the description adds substantial operational context beyond them. It discloses the catalog grouping, per-entry fields, the hard self-serve guard, and the server-side refusal to provision or bill selfServe:false add-ons. It also clarifies sales behavior around the Faber Token Pack and Site Patrol, which is exactly the kind of contextual behavior an agent needs.

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 front-loaded with purpose and catalog structure, then uses clear headings for when to mention add-ons and the self-serve guard. It is longer than a typical catalog-fetch description, but most sentences carry actionable policy or routing information; there is little repetition.

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?

Given the tool's complexity around sales policy, self-serve restrictions, and catalog entry semantics, the description is complete enough for an agent to call it correctly and use the result correctly. No output schema exists, but the description explains the returned fields and the key guardrails in sufficient detail.

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?

The tool has zero parameters, so schema semantics are not a concern and the baseline is 4. The description instead documents return-entry fields such as family, priceDisplay, monthly, oneTime, grantsEdits, selfServe, and appliesToCategories, which is useful context but belongs more to output semantics than parameter semantics.

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 specific verb and resource: fetch the canonical Squish hosting add-on catalog. It clearly distinguishes this catalog from sibling catalogs by naming what it contains (control panels, backups, monitoring, Faber Token Pack) and by explicitly routing Faber plan questions to get_hosting_catalog. An agent can identify the right tool without opening the schema.

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 explicit when-to-use triggers, such as any question about control panels, managed backups, monitoring, or 'can I add' hosting questions. It also names alternatives and exclusions: use get_hosting_catalog for the Faber plan, do not proactively pitch Site Patrol, and route selfServe:false add-ons to sales rather than presenting them as purchasable.

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