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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuine behavioral context beyond that: the exact return contents (name, run counts by status, last run time) and the pagination envelope (50 default, 100 max), which is useful for an agent. It stops short of auth or rate-limit context, 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?

Three short sentences, front-loaded with the use case, followed by scope/return behavior and then the exclusion. Every sentence carries information and nothing is 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?

Covers purpose, project scope, return summary, limit envelope, and an explicit exclusion, which is enough for a low-complexity list tool with only two parameters. Since an output schema exists, the description's recounting of return fields is mildly redundant, keeping it from a full 5.

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%, so both parameters are already documented in the schema. The description's '50 by default and 100 at most' simply restates the limit constraint already in the schema and adds no new semantics. 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 durable workflow definitions and run-count summaries') plus the scoping constraint ('for one CronCool project'). The closing exclusion 'Not for individual runs' cleanly separates it from list_workflow_runs and get_workflow_run without needing 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?

Provides a clear when-to-use trigger ('when the user wants to list durable workflow definitions and run-count summaries') and a when-not ('Not for individual runs'). The alternative tool for runs is only implied, not named, so it falls short of the explicit routing seen in the best examples.

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