gv_read_sms

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

No annotations are supplied, so the description carries the behavioral burden. It does disclose the return shape (sender, text, timestamp, direction), which is valuable with no output schema, and 'Read' implies a non-mutating operation. It says nothing about pagination/ordering behavior beyond the schema's limit default, nor about permission or rate-limit constraints.

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 short sentences with the scope stated first, so it is well front-loaded and free of filler. The second sentence mildly restates 'Read messages' while adding the return-field detail, which is the only minor redundancy.

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 simple three-parameter read tool with fully documented schema and no output schema, the description covers what it does and what it returns. The remaining gaps — explicit differentiation from gv_list_sms and any pagination behavior — are small rather than blocking.

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%, so the schema already explains conversation_id provenance, limit semantics ('most recent', default 50), and the all/unread enum. The description adds no parameter-level detail beyond that, making the baseline 3 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 states a specific verb and resource — reading messages within a single SMS conversation — which is distinguishable from the sibling gv_list_sms (conversation listing) and gv_reply_sms/gv_send_sms (writes). It does not explicitly name those siblings, so it stops short of a 5.

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?

Usage is only implied: the phrase 'within a specific SMS conversation' signals this is the per-conversation read, and the schema notes conversation_id comes from gv_list_sms results. There is no explicit when-to-use statement, no exclusions, and no routing advice against gv_list_sms or gv_mark_read.

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