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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful operational context beyond that: it never merges automatically, it costs $0.05, and it requires an API key. Return format and pagination remain unstated, but the output schema likely covers that.

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, zero waste, with the core action and the no-auto-merge guarantee front-loaded before the cost/auth note. Nothing redundant.

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 read-only preview tool with an output schema, an annotations-covered safety profile, and fully documented params, this is close to complete. The only gap is the absence of explicit routing guidance versus merge_moments and other preview tools.

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 both parameters already document the 'YYYY-MM-DD inclusive' format, so the schema carries the burden. The description adds nothing about the date range semantics (e.g. whether it bounds Moment creation date), which is the baseline-3 outcome.

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 action (group exact duplicates first, then near duplicates) on a specific resource (Moment duplicates), and the preview/review framing separates it from merge_moments. It stops short of explicitly naming the sibling it contrasts with, so the distinction is implied rather than stated.

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 phrase 'for human review' and 'Never merges automatically' imply this is the step before a merge decision, but the description never says when to pick this over merge_moments, delete_moment_preview, or search_moments. Usage context is inferable but not spelled out.

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