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

With no annotations, the description carries the burden and does disclose the key behavioral traits: it is a session-scoped enumeration, it returns only id/title metadata, and it explicitly does not return document bodies. It does not discuss ordering or size limits, which is a minor gap for a read-only list of this kind.

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 and return shape first, then trigger conditions, then the exclusion and next step. Every sentence carries distinct information with no restatement of the name.

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 no-annotation, no-output-schema list tool it covers purpose, return fields, and sequencing, which is nearly everything an agent needs. The only omission is any mention of the notification_message parameter's role, though the schema covers it.

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 the single notification_message parameter is already documented in the schema. The description says nothing about it, so it neither clarifies the surprising fallback-message parameter nor compensates for any gap — 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?

"List all stored PDF drafts in this session" gives a specific verb, resource, and scope, and the return shape (previews[{preview_id, title}], count, most_recent_preview_id) is spelled out. It differentiates from siblings by stating it does not show document body and pointing to get_preview instead.

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?

It names concrete invocation triggers ("user taps List PDFs or asks which drafts exist") and prescribes the follow-up sequence ("follow with get_preview after they pick"), so the agent knows both when to call this and what to do next.

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