brain_search

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

With annotations indicating readOnlyHint=true and destructiveHint=false, the safety profile is already clear. The description adds useful behavioral details: the search is literal and case-insensitive, and the tool returns source-citing output. However, it does not mention limits or edge cases like pagination or behavior with no matches, which would be extra context beyond 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 one focused sentence that front-loads the key distinction ('Literal, case-insensitive search') and immediately states the return value. Every word earns its place; no fluff or redundant restatement of the tool name.

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 is a simple read-only search with annotations covering safety and idempotence, the description is largely complete. The main missing context is the sibling differentiation and explicit behavior for the 'limit' parameter, but the tool's simplicity and annotations reduce the burden. It does not need to explain return values in detail because it already states them.

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 documents only the parameter names and types; description coverage is 0%. The description adds meaning by stating that the search returns file, line number, and matching line, which clarifies the 'query' parameter's effect. It doesn't explain the 'limit' parameter in detail, but a limit's purpose is fairly evident from its integer type and range. A score of 4 is appropriate because the description compensates for the schema's lack of semantic detail on what a query produces.

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 uses a specific verb ('search') and resource ('the brain'), and explicitly states what it returns (file, line number, and the matching line). It clearly distinguishes itself from siblings like brain_list and brain_read by framing itself as a search operation rather than listing or reading.

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 this tool is for locating specific content within the brain, which is distinct from brain_list and brain_read, but it does not explicitly state when not to use it or name alternatives. The phrase 'Literal, case-insensitive search' gives some context on when it is appropriate, but it could more explicitly contrast with sibling tools.

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