search_by_filename

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

With no annotations, the description carries the behavioral burden and does so thoroughly: date_from is inclusive, date_to is exclusive, dates use YYYY-MM-DD ingestion dates, scope has defined values and a fallback default, and the tool is positioned as a non-final step. This is substantive operational context beyond what the schema exposes.

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 front-loaded with purpose and usage, and every sentence adds operational value. It is slightly longer than strictly necessary due to multiple prose paragraphs, but the density of useful guidance is high.

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 6-parameter tool with no schema descriptions, the description covers the core filtering semantics and workflow. It is incomplete only on limit, project_name, and exact/path-matching behavior, which would make invocation fully unambiguous.

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 description meaningfully explains file_path, date_from, date_to, and scope semantics (inclusivity, format, allowed values, default). However, schema description coverage is 0%, so the description is the only semantic source, and it omits limit and project_name entirely, leaving two of six parameters under-specified.

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 opens with a specific verb and resource ('Find prior sessions') and makes clear the input is a file or folder path. It distinguishes itself from search_sessions by contrasting semantic-term queries with path-only queries, so an agent can identify the right tool immediately.

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 explicitly states when to use this tool ('Use when the user asks for changes/history for a specific file or folder and does not provide separate semantic search terms') and when not to ('use search_sessions with file_path instead'). It also documents the follow-up workflow (second step after search_sessions) and warns not to auto-call summarize_session.

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