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

Annotations declare readOnlyHint=true and openWorldHint=false, so the safety profile is already covered. The description adds scope context ('currently active pinned', 'plotted signals', 'Analysis panel'), which tells the agent this reads live UI state rather than raw data. But it says nothing about return format or behavior when nothing is pinned.

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 front-loaded sentence with no waste. Every clause (active, pinned, computed values, plotted signals) 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?

For a small one-param read tool with annotations and no output schema, the description is adequate but thin. It doesn't clarify the shape of 'computed values' or how the panel's pinned state is defined, leaving minor gaps for correct invocation.

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%, and the single optional blockId filter is documented in the schema; the description adds no parameter detail. Baseline 3 applies when the schema carries the parameter semantics.

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 (Retrieves) and resource (pinned measurements and computed values) scoped to the Analysis panel and plotted signals. It's clear what it returns, but it doesn't distinguish itself from related siblings like calculate_metrics, get_signal_data, or get_fft_data that an agent might confuse it with.

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?

No guidance on when to use this versus alternatives such as calculate_metrics or get_signal_data. It implies a read of the current Analysis panel state, but an agent gets no conditions or exclusions to route correctly.

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