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

Annotations already cover read-only, idempotent, non-destructive behavior. The description adds valuable context beyond annotations: pagination ordering, field list, and the tier restriction ('sp500+ (sample rejected)'). This helps the agent understand access and response shape. No contradiction with annotations.

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 concise (two sentences) and front-loaded with the core listing behavior. It packs in pagination, ordering, fields, filter, cross-references, and tier restriction. The 'Tier: sp500+ (sample rejected)' phrase is slightly cryptic but not redundant. Every sentence earns its place, though the density could be improved.

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 tool's simplicity, the description covers all critical aspects: what is listed, ordering, pagination, filtering, and access tier. The output schema exists, so return values are documented separately. The description is complete for an agent to invoke the tool correctly without needing additional 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% for all three parameters (limit, cursor, status) with clear descriptions and defaults. The description's mention of filtering by status and pagination slightly reinforces the schema but does not add new semantic information beyond what the schema already provides. 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 tool lists the caller's signals with a specific set of fields (id, condition, channel, status, trigger_count, evaluator health). It distinguishes from siblings like list_signal_inbox by specifying 'signals' and mentions pagination and filtering, making the purpose unambiguous.

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?

Provides clear context for when to use the tool: to list signals (newest-first, paginated, filterable by status). It explicitly connects the returned signal id to delete_signal and test_signal, giving forward usage direction. It does not explicitly mention alternatives or exclusions, but the context is strong enough for an agent to decide.

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