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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds valuable behavioral context beyond these annotations: MCP has no streaming, the tool doubles as a poll mechanism, and the `since` cursor returns only new or changed rows. This meaningfully clarifies the tool's runtime behavior and pagination contract.

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 three sentences long and every sentence earns its place: the core operation, the critical polling behavior, and the return shape. It is front-loaded with the primary purpose and contains no filler or redundant restatements of the title or annotations.

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 the moderate complexity of cursor-based pagination and polling, the description is complete: it states the return fields, explains how to use `since`, and notes the mutable-collection context. With readOnlyHint and a 100%-covered schema, no critical gaps remain for an agent to invoke the tool correctly.

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%, providing baseline parameter descriptions for all four fields. The description goes beyond the schema by giving `since` rich semantic meaning (poll handle, prior next_cursor, 'only rows that are new or changed'), and by clarifying the response structure ({ rows, next_cursor, has_more }). This adds real value over the schema alone.

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 opens with a specific verb and resource: 'List rows in a v2 app's mutable collection', which clearly identifies the operation and scope. It also differentiates itself from sibling tools like get_row (single row) and list_deleted_rows by focusing on the mutable collection and adding a polling use case.

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 explicitly explains when to use the tool for polling ('This is also how a collection's current state is polled') and how to leverage the `since` cursor for incremental fetches. It does not name alternatives or exclusions (e.g., when to use list_deleted_rows instead), but the context is clear enough for most selection scenarios.

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