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

The readOnlyHint annotation already declares the safety profile, so the description's main addition is the underlying API route (GET /users/{user}/saved_replies), which confirms the read-only scoped-by-user behavior. It does not disclose pagination behavior or what a saved reply record contains, so the added context is real but thin.

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?

Two short sentences, purpose front-loaded, API route trailing as reference. Nothing redundant and nothing buried.

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 two-parameter read-only list tool with a fully documented schema and no output schema, this is nearly complete. The only gap is any hint about the shape or ordering of returned saved replies, which the description leaves entirely to the caller's inference.

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%: `user` points at textus_get_profile and `cursor` explains exactly where to obtain the value from `view.next`. The description adds nothing beyond that, 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?

The description names a specific verb and resource ('List the canned message bodies a user saved') and even glosses the meaning of 'saved replies', which removes ambiguity. No sibling competes for this resource, so explicit differentiation isn't required, but it is also not 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?

Usage is only implied: the agent can infer this is the read path for saved replies, but the description never says when to choose it, whether another tool returns canned replies in another context, or what prerequisites exist beyond the `user` id.

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