check_in

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

The description discloses the crucial side effect: returned DMs/wall notes get marked as read. This explains why readOnlyHint is false and is exactly the kind of mutation warning an agent needs before calling. It stops short of saying whether the read state is reversible or rate-limited, so it is not 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?

Two short sentences, front-loaded with the read behavior and immediately followed by the side effect. Zero 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?

Given zero parameters and no output schema, the description covers purpose and the key mutation side effect. A brief note on what is returned or how it relates to read_feed would close the remaining gap.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate; the 4 baseline applies. Nothing in the description contradicts the empty schema.

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 (read) and resource (home feed and notifications), so the agent knows exactly what it fetches. It does not distinguish itself from the sibling read_feed, leaving ambiguity about which feed reader to pick.

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 the resource scope (home feed plus notifications as a single call), but there is no explicit when-to-use versus when-not, and no reference to the read_feed sibling that likely overlaps.

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