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

Annotations already declare readOnlyHint=true, idempotentHint=true and destructiveHint=false, so safety is covered structurally. The description adds genuinely new operational context beyond that: a hard result cap of 100 projects, which tells the agent to consider pagination or narrowing. It does not discuss auth scoping or ordering, but the annotations carry most of the behavioral burden.

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?

Two sentences with the use case front-loaded, then the exclusion. Every clause earns its place and nothing is repeated from the title or annotations.

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 output schema exists, so return-value shape is already machine-documented, and the description still adds the useful 100-project bound. For a zero-parameter, read-only list tool, an agent has everything needed to call it correctly and know its limits.

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 takes zero parameters and the schema has no properties, so there is nothing for the description to disambiguate. Baseline for a no-parameter tool is 4; the description adds no parameter guidance because none is needed.

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 a specific verb+resource ('List your localization projects') scoped to the caller's own projects, and enumerates the returned fields (id, name, default locale, languages, timestamps). The closing clause explicitly distinguishes it from the string-listing siblings, so an agent can separate it from list_phrases without opening either 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?

'Use this when someone asks which localization projects they have' gives an explicit triggering condition, and 'Not for listing the strings inside a project' gives a clear exclusion. It stops short of naming the alternative tool (e.g., list_phrases) directly, leaving the agent to map the exclusion to a sibling.

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