get_completions

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

With no annotations provided, the description discloses an important behavioral constraint: the file must be opened first. It also clarifies that completions are context-based. However, it does not describe return format, error conditions, or whether an LSP server must be running, so it only partially covers transparency.

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 composed of five sentences but contains redundancy: sentences 1 and 2 both describe retrieving completions, and sentence 3 ('Helpful for...') adds little. The useful unique information (use case and prerequisite) could be expressed in fewer words.

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 completion tool, the description covers the core purpose, context, example use case, and a critical prerequisite (open file). It omits details about the return value or error handling, but given the simplicity and lack of output schema, it is reasonably complete for an agent to select and invoke the tool.

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 schema already documents all four parameters with 100% coverage, so the baseline is 3. The description indirectly references location and context but does not add specific parameter details beyond what the schema provides. The prerequisite about opening the file adds a bit of context for file_path.

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 clearly states the main function ('Get completion suggestions at a specific location in a file') and elaborates on the types of completions (variable names, function calls, object properties). This distinguishes it from siblings like get_diagnostics or get_code_actions, which have different purposes.

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?

It provides explicit use cases ('when determining which functions you have available in a given package, for example when changing libraries') and a prerequisite ('Requires the file to be opened first'). However, it does not explicitly name alternative tools or say when not to use it, so it is not a full 5.

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