trace_add_spans

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

With no annotations provided, the description must fully disclose behavioral traits. It only says 'Add custom spans and attributes,' which implies a code-modifying operation, but it does not mention whether files are modified, whether an OpenTelemetry setup is required, what side effects occur, or how authentication via api_key is used. Minimal behavioral context is provided.

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?

A single, clear sentence with no filler words. The action and target are front-loaded and every word contributes meaning. It is concise without sacrificing core purpose.

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?

The description is too thin for a mutating tool with no annotations and no output schema. It does not explain return behavior, file/system side effects, dependency on an existing tracing setup, or whether this tool should be called before or after trace_setup_otel. An agent would need to infer most context.

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 coverage is 100%, so all parameters are already described in the schema. The description adds the context of 'instrument critical code paths' but does not clarify how operations, language, or service_name map to span/attribute generation beyond what the schema already states.

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 a specific verb ('Add'), a specific resource ('custom spans and attributes'), and the goal ('instrument critical code paths'). It distinguishes itself from setup/configuration siblings like trace_setup_otel and trace_configure_export by focusing on adding spans, though it does not name any sibling explicitly.

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?

There is no guidance on when to use this tool versus alternatives such as trace_setup_otel or trace_configure_export. The phrase 'to instrument critical code paths' implies use during instrumentation, but it does not state prerequisites, exclusions, or when another tracing tool would be more appropriate.

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