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 still adds useful reinforcement that "Listing sends nothing" — a real concern an agent might have when a listing is one step from replying — and discloses the returned fields (name and content) despite there being no output schema. It stops short of stating pagination or result-count behavior, which keeps it from a 5.

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, front-loaded with purpose, then the usage trigger, then the hand-off to reply_to_comment. Every sentence carries distinct information — definition, when to consult, and what to do next — with no restated title 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?

For a single-parameter read tool with no output schema, the description covers what it does, what it returns at a field level, the fact it has no side effects, and where the result flows next. Nothing an agent needs in order to call it correctly is missing.

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?

There is a single parameter with 100% schema description coverage, and the schema already says workspace_id is required and points to list_workspaces. The description adds no further meaning about that parameter, so the baseline 3 for fully documented schemas 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 ("Lists the workspace's saved replies for the inbox") and immediately defines the domain concept as "reusable reply text the team has written, each with a name and content." That definition separates it cleanly from nearby siblings like list_comment_dm_rules or list_inbox_conversations without the agent needing to open any schema.

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?

Gives an explicit when-to-use trigger ("Check this before drafting a reply to a comment or DM") plus the action rule ("use a saved reply when one fits, adapted to the message"). It also names the correct downstream tool for the actual send ("pass the final text to reply_to_comment"), which is genuine alternative/replacement guidance.

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