lsp-mcp-server

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

Annotations provide readOnlyHint=true, openWorldHint=false, and idempotentHint=true, indicating safe, deterministic reads. The description adds valuable context beyond this: it specifies that diagnostics are 'cached' (implying they may not be real-time) and come from 'language server notifications' (clarifying the source). This enhances transparency without contradicting annotations.

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 two sentences, front-loaded with the core purpose and followed by clarifying context. Every word earns its place, with no redundancy or unnecessary elaboration, making it highly efficient and easy to parse.

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?

Given the tool's moderate complexity (2 parameters, no output schema), annotations cover safety and determinism, and the description adds caching and source context. However, it lacks details on return format (e.g., structure of diagnostics) or error handling, leaving minor gaps for a tool without an output schema.

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%, with clear parameter documentation. The description adds minimal semantics beyond the schema, mentioning 'errors, warnings' which aligns with severity_filter but doesn't provide additional details like format or examples. Baseline 3 is appropriate since the schema already fully describes parameters.

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 action ('Get cached diagnostics') and resource ('for a file'), specifying that diagnostics include errors and warnings from language server notifications. It distinguishes from siblings like lsp_code_actions or lsp_format_document by focusing on diagnostic retrieval rather than code fixes or formatting.

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 for accessing diagnostics but doesn't explicitly state when to use this tool versus alternatives like lsp_hover or lsp_completions. It mentions diagnostics come from language server notifications, suggesting it's for post-analysis retrieval, but lacks clear exclusions or comparative guidance with sibling tools.

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