Mark Submission Read

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

Annotations already declare this is a non-destructive, open-world write, so the description needn't restate safety. It adds real context beyond them by naming the exact state change (read flag/unread badge) and the blast radius ('Only affects you'), which is what an agent needs before mutating state on a shared 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?

Two short sentences, the core action front-loaded and the scope caveat second. Nothing is redundant or padded.

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-required-param mutation with full schema coverage and no output schema, the description supplies the action, the effect, and the scope limit. A slightly fuller treatment of edge cases (already-read submissions, error behavior) 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?

Schema description coverage is 100%, and both parameters (course_id, assignment_id) already include format hints and the sibling tools to fetch their values from. The description adds nothing about parameters, so 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?

States a specific verb (mark ... as read) plus a specific resource (your submission), and adds the observable effect (unread badge clears). The resource is distinct from the many other mark_*_read siblings, so an agent can identify it without opening the 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?

Usage is implied rather than stated: you call it when a submission has a new grade or comment and you want the badge gone. No alternatives or exclusions are named, and it doesn't say what to do if nothing is unread. 'Only affects you' gives a useful scope cue but isn't a when-to-use rule.

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