get_function_by_name

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description does not need to repeat safety traits. It adds value by specifying that the tool returns 'purpose, parameters, returns, and file path', which is behavioral context beyond what annotations provide. No contradictions.

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 a single sentence with no wasted words. It front-loads the action ('Look up') and immediately provides the usage hint and return information. Every part of the sentence is informative and earns its place.

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 parameters (3, all with schema descriptions), rich annotations (readOnlyHint, idempotentHint), and no output schema, the description adequately covers what the agent needs: the tool's purpose, when to use it, and what it returns. No gaps are apparent.

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 input schema has 100% description coverage, so the parameters are well-documented in the schema itself. The description does not add new meaning to individual parameters beyond what the schema provides, but it does set overall context for when to use the parameters. Baseline 3 is appropriate.

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 ('Look up'), the resource ('tracked function by name'), and the returned data ('purpose, parameters, returns, and file path'). It also includes a usage hint ('use BEFORE reading source files'), which distinguishes it from sibling lookup tools like search_functions or get_functions_by_file.

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 explicitly advises to use this tool before reading source files, providing a clear usage context. It does not explicitly mention when not to use or name alternatives, but the timing guidance is actionable and helps the agent sequence operations correctly.

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