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

Annotations already declare readOnlyHint=true, destructiveHint=false, so safety is covered; the description reinforces this with 'sends nothing' and adds a genuinely new behavioral constraint, the 24-hour lookback window. It does not describe whether the preview is rate-limited or how large the preview can get.

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?

Three short sentences, purpose front-loaded, no filler. Each sentence carries distinct information: what it does, the no-send guarantee, sequencing, and alternative routing.

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?

For a one-parameter read-only preview with no output schema, the description conveys the temporal scope and what the preview represents. It stops short of describing the preview's shape (e.g., counts vs. full email bodies), which is the only meaningful gap.

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% and the single view_id parameter is already documented as a UUID sourced from list_views. The description's phrase 'one View' and 'owner's current settings' adds only marginal context beyond the schema, so the baseline 3 applies.

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 precise verb and resource: it previews what a View would have emailed in the last 24 hours, under current owner settings. It also distinguishes itself from list_matches, which answers the different question of what was actually recorded/sent.

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 explicit sequencing ('Call it after create_view or update_view') and routes a neighboring use case to the correct sibling ('Use list_matches for the Matches it recorded and whether each was sent'). An agent knows both when to call it and when to call something else.

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