search_spans

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

With no annotations, the description carries the full behavioral burden. It does usefully disclose the search substrate (span names and attributes, not span IDs or payloads), which goes beyond the schema, but it says nothing about case sensitivity, whether the search spans all runs or one, result limits, or ordering. It is a read-only search by implication only.

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 tight sentence with the verb and resource front-loaded and the illustrative examples compactly bracketed at the end. No filler, no 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?

An output schema exists, so return values need not be explained, and the description correctly covers the core search semantics for a two-parameter tool. The unaddressed trace_id scoping is the only substantive hole for an agent deciding between a global and a trace-scoped search.

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% and there are two parameters. The examples give real meaning to 'needle' (substring matched against names/attributes), but 'trace_id' — the parameter that scopes the search — is never mentioned, leaving a meaningful gap the schema does not fill.

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?

States a specific verb and resource — substring search over span names/attributes — and clarifies what a 'needle' can be with concrete examples (tool name, file path, 'denied'). It does not distinguish itself from sibling diagnostics like span_tree or failure_report, so an agent gets no routing comparison.

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 examples describe what values to search for, not when to choose this tool over alternatives such as span_tree or failure_report. There is no when-to-use, when-not-to-use, or prerequisite guidance; the agent must infer the use case from the tool name alone.

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