search_calls

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

Annotations already declare read-only and idempotent behavior, so the bar is lower. The description adds useful context beyond annotations: it searches only function names, returns counts/call numbers rather than full dumps, and implies a lightweight operation ('cheapest way').

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?

Two sentences deliver purpose, return shape, and a practical example with no filler. The front-loaded first sentence tells the agent exactly what the tool does, and the second sentence earns its place by showing a real regex use-case.

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 provides good high-level context and an output schema exists to document return values. However, with five parameters and zero schema-level parameter documentation, important invocation details remain underspecified, especially the role of the optional 'calls' parameter and whether matching applies to substrings or full function names.

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%, so the description must compensate. It does clarify that 'pattern' is a regex over function names and gives a concrete example, but it leaves 'trace', 'calls', 'timeout', and 'max_hits' unexplained; 'calls' in particular is ambiguous.

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 ('Regex search') and resource ('function names across the trace') and states the return form ('counts and call numbers'). It is clear on its own, but it does not name or contrast sibling tools like dump_calls, get_calls, or call_histogram, so differentiation is left to inference.

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 gives a concrete diagnostic use-case and explicitly frames this tool as the cheapest way to detect fixed-function vs. shader-constant usage, with an example pattern. It stops short of naming alternatives or saying when not to use it.

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