list_emails_year

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

No annotations are provided, so the description carries the full burden. It discloses key behavioral traits: the time-based filtering, sorting order ('newest-first'), return format (array of objects with specific fields), and that the id is globally unique for use with another tool. However, it doesn't mention potential limitations like pagination, rate limits, or authentication needs, which are relevant for a list operation.

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 the core purpose, followed by return details and a usage tip, all in three concise sentences with zero waste. Each sentence adds value: the first defines scope, the second specifies output, and the third provides context for the id field.

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 no annotations and no output schema, the description compensates well by explaining the return format and sorting, and it references another tool for extended functionality. For a simple list tool with one parameter, it's mostly complete, but lacks details on error handling or performance aspects like result 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?

Schema description coverage is 100%, so the schema already documents the single parameter 'mailbox' with its type and default. The description does not add any information about parameters beyond what the schema provides, such as explaining mailbox options or constraints. Baseline 3 is appropriate as the schema handles parameter documentation adequately.

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 ('List'), resource ('emails'), and scope ('received in the last 365 days'), distinguishing it from siblings like list_emails_24h or list_emails_all by specifying the time range. It explicitly mentions the output format, which helps understand what the tool returns.

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 explicit guidance on when to use this tool by specifying the time range ('last 365 days') and mentions an alternative tool ('fetch_email_content') for reading full emails, helping differentiate it from other list_emails_* siblings. It implies usage for recent email retrieval without filtering by sender or domain.

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