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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so safety is covered. The description adds real behavioral context beyond that: the threading model (depth and parent id), the fields returned (text, author, upvotes, date), and the cost model ('1 point per returned record').

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?

A single front-loaded sentence carrying the operation, threading, and returned fields, plus a short pricing clause; no redundancy. Efficient and well-ordered.

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 read-only list tool with full annotations and no output schema, the description covers operation, return fields, and threading adequately; pagination lives in the schema. Minor gap: no note on how threading interacts with pagination, but nothing essential 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?

Schema description coverage is 100%, so the schema already documents post, max_items and start_page thoroughly. The description only gestures at the 'one post' scope and adds no syntax or format detail beyond the schema, so the baseline 3 is appropriate.

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+resource ('List the comments of one Indie Hackers post') and even outlines the returned fields and threading model, distinguishing it clearly from run_indiehackers_posts. It doesn't explicitly name the sibling it complements, but the resource distinction is unambiguous.

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 implied by 'one Indie Hackers post' and the required post parameter, so an agent can infer this needs a post slug/URL. However there is no explicit when-to-use guidance or comparison against alternative comment/thread tools nearby.

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