access-shared-mailbox

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

Annotations already declare readOnlyHint=true, so the description's mention of 'read-only' is consistent but not additional. The description adds behavioral context: paged returns, same shape as search-emails, defaults for folder and count, and outputVerbosity for detail control. This is sufficient, though rate limits or error conditions are not mentioned.

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 concise at about 4 lines, with no redundant sentences. It is front-loaded with the core purpose and then provides necessary details in a logical order. Every sentence adds value.

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?

Despite lacking an output schema, the description explains the return shape (id/subject/from/receivedDateTime/preview) and references the sibling tool's list mode. It covers prerequisites, parameter defaults, and alternatives. For a list tool with this complexity, the description is fully adequate.

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 baseline is 3. The description adds meaning by explaining the purpose of 'email' as an alias for 'sharedMailbox', default values for 'folder' and 'count', and the role of 'outputVerbosity' with its enum options. This extra context justifies a score 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?

The description clearly states the tool's action ('List emails'), resource ('shared mailbox'), and read-only nature. It distinguishes itself from sibling tools by referencing 'search-emails' as an alternative for full search/filter capability.

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 (list emails from a delegated shared mailbox) and when to use an alternative ('prefer search-emails with a folder path scoped to the shared mailbox' for full search/filter). It also mentions the prerequisite that the mailbox must be admin-configured and delegated.

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