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

Annotations only declare it is a safe, idempotent, closed-world read. The description goes far beyond that: it discloses entitlement truncation (first 5 rows + locked.count/locked.by_type, never the rows), that contact values and decision-maker names are suppressed to types and counts, and that every response carries `entitlement` and `locked` keys. This is exactly the behavioral context annotations cannot carry.

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?

Purpose is front-loaded in the first clause and the entitlement caveat is separated cleanly. The dense, deeply nested parenthetical that enumerates each entity type's sections is heavy, but every clause carries real information rather than filler.

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?

With no output schema, the description fully describes the return shape per entity type plus the relationship/event/evidence/cross-graph-link sections and the truncation metadata. An agent knows what it will receive and what will be withheld, leaving nothing essential unstated.

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 100% and the schema already documents the full dfx id prefix vocabulary, so the description need not re-explain it. The description's 'Accepts dfx:isi: ids' adds only a scoping hint for this tool's graph, which is marginal value over the schema baseline.

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: 'the full card for any entity on the sponsor graph', then enumerates the three subjects (sponsor, capital provider, private company) and the sections each returns. An agent can distinguish this detail lookup from list/search siblings like search_independent_sponsors without opening a schema.

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 'Accepts dfx:isi: ids' note and the title imply this is the point-lookup companion to search_independent_sponsors, so usage is inferable. However, no explicit when-to-use, when-not-to-use, or named alternative is given; the ACCESS block is about plan entitlements, not tool selection.

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