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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description goes beyond them with genuinely useful behavior: pagination is a page rather than a total count with a nextCursor continuation, summaries may contain caller-provided PII and are untrusted data (a prompt-injection warning), and a missing summary is null. Those additions are valuable, but return shape is largely carried by the output schema, so this sits at a solid but not maximal level.

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?

Front-loads the core action and scope in the first sentence, then sequences ordering, inclusion set, pagination, data-trust warning, null handling, and exclusions. Every sentence carries distinct information with no repetition or filler.

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?

With annotations covering safety and an output schema covering the return shape, the description fills the remaining gaps an agent needs: pagination model, continuation parameter usage, inclusion of archived/spam/missed, null-summary handling, and an explicit untrusted-content caution. Nothing material is missing for correct invocation.

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 both parameters (limit and cursor) are already fully documented with defaults, bounds, and the opaque nextCursor semantics. The description's 'pass nextCursor to continue' restates what the cursor schema field already says and adds no new syntax or format detail, so 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 specific verb and resource ('List saved calls and their stored summaries'), names the scope ('connected Tinylawn organization'), and specifies ordering ('newest first') plus inclusion of archived/spam/missed calls. There are no sibling tools to confuse it with, and the one-line negative clause ('does not read transcripts or recordings') further pins the boundary of what is listed.

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?

Explicitly enumerates what the tool does not do: read transcripts or recordings, filter by date, modify calls, mark them read, confirm appointments. That gives an agent clear when-not conditions and prevents misuse for filtering or transcript retrieval, which is unusually thorough guidance.

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