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chrome_page_load_resource_pipeline

Read-onlyIdempotent

Drill into a Chrome page-load resource URL to join lifecycle and request spans with script, style, and layout signals for detailed timing and matching evidence.

Instructions

Drill into one Chrome page-load resource URL and join lifecycle/request spans with script/style/layout signals. Use after chrome_page_load_resource_summary with example_slice_id or url_substring. Returns timing facts, match evidence, resource ends, primary/detail slice evidence (detail is not a root-cause claim), URL/ancestor-correlated resource result source/hit, machine-id sets, incomplete count, and evidence_boundary. Parameters: URL seed required; optional window filters, url_grouping, limit default 30, max_string_len.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
end_ts_nsNoOptional raw trace timestamp upper bound in nanoseconds, exclusive. ANDs with any page-load window.
example_slice_idNoOptional resource-summary/hotspot `example_slice_id`; when provided the tool derives that slice's URL and drills into matching URL rows.
limitNoOptional max rows to return. Defaults to 30 and is capped at 5000. Must be > 0 when set.
max_string_lenNoOptional per-string-cell character cap applied to returned rows only. Unset preserves full strings for precision; accepts both numbers and numeric strings. Must be > 0 when set.
navigation_idNoOptional Chrome navigation id used to scope resources/scripts to one navigation phase. Matches `chrome_page_loads.navigation_id`. Mutually exclusive with `page_load_id`. If set without `phase`, defaults to `navigation_to_fcp`.
page_load_idNoOptional page-load id used to scope resources/scripts to one navigation phase. Matches `chrome_page_loads.id`. Mutually exclusive with `navigation_id`. If set without `phase`, defaults to `navigation_to_fcp`.
phaseNoOptional page-load phase window. If set without `page_load_id` or `navigation_id`, uses the latest page load in the trace. Values: navigation_to_fcp, navigation_to_load, dcl_to_fcp, fcp_to_load.
start_ts_nsNoOptional raw trace timestamp lower bound in nanoseconds. ANDs with any page-load window.
url_groupingNoURL grouping strategy. Defaults to full URL; use without_query to merge signed/nonce query variants of the same endpoint.
url_substringNoOptional URL substring to drill into, e.g. "main.js" or "qianwen-web-desktop/2.3.401/js/main.js". Matches against URL-bearing resource and script slices with SQL INSTR, not LIKE wildcards.

Tool Definition Quality

A4.1/5.0
Behavior4/5

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

Annotations already indicate read-only and idempotent behavior; description adds return fields and notes that detail is not a root-cause claim, providing useful context beyond annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Description is concise and front-loaded with the main action, though the single sentence is dense and could be slightly better structured for readability.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given 10 parameters and no output schema, the description provides a reasonable overview of return fields and usage context, though not exhaustive.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so baseline is 3. Description mentions URL seed conceptually and groups parameters, but adds little extra meaning beyond the schema definitions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool drills into a specific Chrome page-load resource URL and joins lifecycle/request spans with script/style/layout signals, distinguishing it from the sibling summary tool.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly advises using after chrome_page_load_resource_summary and provides two methods (example_slice_id or url_substring) to specify the resource, but does not mention when not to use it or alternatives.

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

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