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

Beyond the readOnlyHint/destructiveHint annotations, the description discloses substantial behavior: both modes honor path, recursive toggles one-level vs whole-subtree, return shape is always the same, recursive vs non-recursive entry naming differs, and a nonexistent ref is an error. This is rich, non-obvious context that helps the agent predict outcomes.

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?

The description is compact and front-loaded, with the core action in the first sentence and every subsequent sentence adding distinct information about modes, return shape, or error behavior. No filler or redundant restatement.

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 present, the description wisely defines the exact return shape. It covers path behavior, recursive behavior, entry naming, and ref errors. Minor gaps remain, such as what truncated means or how pagination works, but these are not essential for a basic correct invocation.

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 only 40%, but the description compensates by explaining the two most behaviorally important parameters: path scoping and recursive semantics. It also adds meaning for ref by stating that a missing ref is an error. Only owner and repo are left to the schema, but those are standard repository identifiers and require little additional explanation.

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?

The description opens with a specific verb and resource: 'List directory contents at a ref.' This clearly distinguishes it from sibling tools like gluecron_read_file and gluecron_find_symbol, which serve different purposes. The focus on directory listing is unambiguous.

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 gives clear context for when to use the tool and how its modes behave: path scopes to a subtree, recursive walks the whole subtree. It does not explicitly name alternatives or state when not to use it, but the directory-listing purpose is enough for an agent to select it correctly in most cases.

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