list_installed_hdas

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states that the tool lists installed HDA files and their definitions, which is a read-only operation, but it doesn't disclose whether the list is sorted, whether it includes built-in versus user HDAs, whether it triggers a cook or scan, or what the return structure looks like. The description is minimal and leaves the agent without important behavioral context.

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 concise and front-loaded with the main purpose in the first sentence. The Args section is minimal and directly relevant. It earns its place by documenting the filter parameter, which is the only parameter. No wasted words, though the 'ctx: MCP context' line is boilerplate that adds little value.

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 simple list tool with one optional parameter and no output schema, the description is mostly adequate. However, it lacks information about the return format (e.g., list of names, paths, definitions), which an agent would need to use the results. It also doesn't mention whether the tool is read-only or whether it requires a specific context. Given the simplicity, a 3 is appropriate – it's usable but has clear gaps.

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 0%, so the description must compensate for the undocumented 'filter' parameter. The description does add meaning by saying 'Substring filter for type names or file paths,' which clarifies the parameter's purpose and acceptable values. However, it doesn't specify case sensitivity, matching behavior, or whether the filter applies to both type names and file paths simultaneously. The baseline is 3 because the description adds some value beyond the schema, but not comprehensive semantics.

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 states a clear verb and resource: 'List all installed HDA files and their definitions.' This distinguishes it from related HDA tools like install_hda, uninstall_hda, reload_hda, and get_hda_info. However, it doesn't explicitly differentiate itself from list_hda_versions, which could be a sibling with overlapping scope.

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 implies usage by naming the operation and the optional filter, but it doesn't explicitly state when to use this tool versus alternatives like list_hda_versions or get_hda_info. There is no exclusion guidance or mention of prerequisites, so the agent must infer the appropriate context from the tool name and sibling list.

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