Serena MCP Server

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

No annotations are provided, so the description carries the full burden. It discloses key behavioral traits: it filters out gitignored files (a critical constraint), returns a JSON object with a list, and searches within a relative path. However, it doesn't mention performance characteristics (e.g., speed, recursion depth), error handling, or what happens with invalid inputs, leaving gaps for a tool with no annotation support.

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 the return format. Every word earns its place—no redundancy or fluff. It's efficiently structured for quick comprehension by an AI agent.

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, no annotations), the description is reasonably complete. It covers the purpose, key constraint (non-gitignored), and return format. However, it lacks details on output structure (e.g., what fields are in the JSON) and error cases, which could be helpful since there's no 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%, so the schema already fully documents both parameters (file_mask and relative_path). The description adds no additional parameter semantics beyond what's in the schema (e.g., it doesn't explain wildcard syntax further or provide examples). With high schema coverage, the baseline is 3, and the description doesn't compensate with extra value.

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 specific action ('Finds'), resource ('non-gitignored files'), and scope ('matching the given file mask within the given relative path'), distinguishing it from siblings like list_dir (which lists all files) or search_for_pattern (which searches content). It explicitly mentions what gets excluded (gitignored files), which is a key differentiator.

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 provides clear context for when to use this tool (searching for files by name/mask in a directory) but doesn't explicitly state when not to use it or name alternatives. For example, it doesn't contrast with list_dir (which lists all files without filtering) or search_for_pattern (which searches within file content), though the purpose implies these distinctions.

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