add_pattern

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

With no annotations, the description fully covers behavioral details: immediate indexing, persistence in config.yaml for future runs, the requirement that the project must already exist, and the return value format (confirmation with counts or error). This goes well beyond a minimal statement.

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 well-structured with a clear intro, usage guidance, parametrized args, returns, and examples. Each sentence is purposeful and there is no filler.

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 tool accepting 4 parameters, it covers all of them, explains side effects (immediate indexing and persistence), provides return behavior, and includes two examples. Since an output schema exists, it doesn't need to elaborate on return types further.

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 and does. Every parameter is explained with meaning, format, and context: project must exist, pattern is relative with an example, type lists valid values, and description is optional. This adds substantial value beyond the bare schema.

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: 'Add a glob pattern to an existing project and index matching files immediately.' It specifies the resource (existing project) and the mechanism (glob pattern), and distinguishes from sibling tools like add_folder/add_file by emphasizing pattern-based indexing rather than concrete paths.

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 gives explicit guidance: 'Use this when you want to index a specific set of files by pattern rather than pointing at a concrete folder path.' This provides a when and when-not, but it does not name the alternative sibling tool (e.g., add_folder), so it stops short of a perfect 5.

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