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

readOnlyHint already tells the agent this is a safe read, so the description correctly spends its words elsewhere: it discloses the ordering guarantee ('most severe first'), the data vintage ('latest scan'), and a key returned field (issue_id). It doesn't cover result volume or pagination, so 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, zero filler, with the scope and ordering front-loaded and the follow-up hint last. Every clause carries information.

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?

With no output schema, the description does the right work by naming issue_id and the sort order, which is enough to chain into explain_issue. Minor gap: no mention of the severity parameter or result limits, which an agent might need to know before calling.

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 coverage is 100%, so both 'site' and the severity enum with its 'minimum severity' semantics and default are already documented. The description adds nothing about parameters — notably it never mentions the severity filter, which is the main lever for shaping results. 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 and resource ('List open issues') plus two scoping constraints: the latest scan and a single site. It stops short of explicitly distinguishing itself from siblings like get_report or get_site_status, but the resource is concrete enough to route on.

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?

Implies the use case ('from the latest scan of one of your sites') and points forward to explain_issue for per-issue detail, which is useful follow-up routing. However, it never says when to choose get_report instead of this tool, nor any prerequisites such as needing a prior scan.

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