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

Beyond the readOnly/destructive/openWorld annotations, it discloses a quota constraint ('Counts against the project's daily fetch cap'), pagination mechanics ('Pages of up to 1000 keys'), and the return shape including plural objects. These are behavioral facts the annotations do not carry, so it adds genuine value.

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?

Front-loads the core purpose, then layers paging, flags, quota, and the endpoint. Every clause carries information, though the trailing raw endpoint path is slightly redundant with the purpose statement. Dense but well-ordered.

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?

With no output schema, the description correctly compensates by describing return values (key id, key path, translation as string/array/plural object) and covers pagination and quota for a 9-parameter tool. It omits error behavior, but for a read-only listing call it is essentially 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 description coverage is 100%, so the schema already documents every parameter and the baseline is 3. The description adds meaning by explaining how `next` chains pages, the 1000-key page ceiling, and the semantics of extra_info/no_content in relation to the returned data, lifting it above baseline.

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+scope: 'Read the strings of one file in one language', and enumerates the returned fields (key id, key path, translation shape). This clearly separates it from siblings like localazy_list_files or localazy_list_key_links, which cover different resources.

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?

Gives concrete usage context for the paging and flag parameters ('pass `next` for the following page', 'Set extra_info for hidden/limit/deprecated/comment', 'no_content to list keys without text'). It does not name a competing sibling or state when NOT to use this tool, so it falls short of explicit alternative routing.

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