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

Annotations already declare readOnlyHint=true, destructiveHint=false and idempotentHint=true, so the safety profile is covered. The description adds genuinely new behavioral context: the sidebar cannot run jobs or modify configuration, and request payloads, full target URLs, secrets and workflow bodies are deliberately excluded from what is shown.

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 sentences, no filler. What the sidebar shows comes first, followed by the read-only constraint and the exclusion list, so the most decision-relevant information is front-loaded.

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 an output schema present, the description does not need to explain return values, and it correctly limits itself to scope, read-only status and data exclusions. The only omission is a pointer to programmatic siblings for agents that cannot use a sidebar view.

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 and schema coverage is 100%, so there is nothing for the description to clarify about inputs. The baseline for a parameterless tool is 4.

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 ("Open Croncool") plus the scope of what the view contains: owned projects, scheduled jobs, target origins, schedules and latest execution status. It is clearly not a data-fetch or mutation tool, so an agent can distinguish it from siblings like list_jobs or run_job by inference, but it never names an alternative explicitly.

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 description establishes the context of use (browsing/reviewing) and the hard constraint that this sidebar is read-only and cannot run jobs or change configuration, which implies when it is appropriate. However, it never states when an agent should prefer this over programmatic siblings such as list_projects or list_jobs, leaving the choice to inference.

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