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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely new context: the data comes from the official Slack Status API (authoritative source, live network dependency) and that it returns active incidents as well as current status. It omits return shape and severity vocabulary, which keeps it below 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?

Four short sentences, front-loaded with the purpose before the mechanism and cost. Slight redundancy between 'Verify if Slack is experiencing connectivity issues' and 'fetches the current status and active incidents', but no filler otherwise.

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 zero-parameter read-only probe with full annotation coverage, this is nearly complete: source, scope, and cost are all stated. The only gap is a hint about what the response contains structurally (e.g., status indicator plus incident list), which matters slightly since there is no output schema.

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; baseline for a no-param tool is 4. The description correctly implies no input is needed by framing the call as a direct fetch.

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 ('fetches the current status and active incidents') scoped to Slack, and explicitly lists the covered surfaces (messaging, calls, file uploads). Against siblings like discord_status or cloudflare_status, the Slack scope is unambiguous from the name and first sentence.

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?

The opening sentence implies the use case ('verify if Slack is experiencing connectivity issues'), which is enough to know when to call it. However, there is no explicit guidance on when not to use it or which sibling status tool to pick when the user's question is ambiguous, and no mention of how often to re-poll during an incident.

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