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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safe-read profile is covered. The description adds useful context about what is returned (purpose, access state, inputs, next action), which is behaviorally informative. Annotations carry much of the safety burden, and the description complements them well.

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, compact sentence that front-loads the core purpose and lists the key return fields. Zero filler, every clause earns its place. The output is immediately scannable.

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 tool is simple: one parameter, read-only, single-entry scope. The description covers what it returns and the schema covers the ID. An output schema exists, so return-value explanation is unnecessary. Minor gap: no explicit mention of error behavior for invalid/nonexistent entry IDs, but this is a minimal omission for such a simple 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 coverage is 100% with a single required parameter. The schema itself describes entry_id as 'the catalog entry identifier from catalog.list or catalog.describe', which is self-documenting. The description confirms the tool operates on 'one catalog entry,' reinforcing the singularity. With a single fully-documented parameter, baseline is high.

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 clearly states the verb+resource ('Return the purpose, access state, inputs, and next action for one catalog entry'). It distinguishes from siblings like catalog_list (listing all entries) and catalog_request/catalog_preview (different actions on a catalog entry). However, it doesn't explicitly contrast with these siblings, so it doesn't reach a 5.

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 implies use case: to get details about a single catalog entry. The parameter doc points to catalog.list or catalog.describe as sources for the ID, which provides some contextual guidance. But there's no explicit statement of when to use this vs catalog_list/catalog_preview/catalog_request, and no exclusions for alternative tools.

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